Aptitude - Technical Questions

1. A 2MB PCM(pulse code modulation) has
 a) 32 channels
b) 30 voice channels & 1 signalling channel.
c) 31 voice channels & 1 signalling channel.
d) 32 channels out of which 30 voice channels, 1 signalling channel, & 1 Synchronizatio channel.
Ans: (c)


2. Time taken for 1 satellite hop in voice communication is
 a) 1/2 second
b) 1 seconds
c) 4 seconds
d) 2 seconds
Ans: (a)


3. Max number of satellite hops allowed in voice communication is :
 a) only one
b) more han one
c) two hops
d) four hops
Ans: (c)


4. What is the max. decimal number that can be accomodated in a byte.
 a) 128
b) 256
c) 255
d) 512
Ans: (c)


5. Conditional results after execution of an instruction in a micro processor is stored in
 a) register
b) accumulator
c) flag register
d) flag register part of PSW(Program Status Word)
Ans: (d) 

6. Frequency at which VOICE is sampled is
a) 4 Khz
b) 8 Khz
c) 16 Khz
d) 64 Khz
Ans: (a)


7. Line of Sight is
 a) Straight Line
b) Parabolic
c) Tx & Rx should be visible to each other
d) none
Ans: (c)


8. Purpose of PC(Program Counter) in a MicroProcessor is
 a) To store address of TOS(Top Of Stack)
b) To store address of next instruction to be executed.
c) count the number of instructions.
d) to store base address of the stack.
Ans: (b)


9. What action is taken when the processor under execution is interrupted by a non-maskable interrupt?
a) Processor serves the interrupt request after completing the execution of the current instruction.
b) Processor serves the interupt request after completing the current task.
c) Processor serves the interupt request immediately.
d) Processor serving the interrupt request depends upon the priority of the current task under execution.
Ans: (a)


10. The status of the Kernel is
a) task
b) process
c) not defined.
d) none of the above.
Ans: (b)

11. To send a data packet using datagram , connection will be established
a) before data transmission.
b) connection is not established before data transmission.
c) no connection is required.
d) none of the above.
Ans: (c)

12. Word allignment is
a) alligning the address to the next word boundary of the machine.
b) alligning to even boundary.
c) alligning to word boundary.
d) none of the above.
Ans: (a)


13 When a 'C' function call is made, the order in which parameters passed to the function are pushed into the stack is

a) left to right
b) right to left
c) bigger variables are moved first than the smaller variales.
d) smaller variables are moved first than the bigger ones.
e) none of the above.
Ans: (b)
14 What is the type of signalling used between two exchanges?

a) inband
b) common channel signalling
c) any of the above
d) none of the above.
Ans: (a)
15 Buffering is

a) the process of temporarily storing the data to allow for small variation in device speeds
b) a method to reduce cross talks
c) storage of data within transmitting medium until the receiver is ready to receive.
d) a method to reduce routing overhead.
Ans: (a)

16. Memory allocation of variables declared in a program is
a) allocated in RAM.
b) allocated in ROM.
c) allocated on stack.
d) assigned to registers.
Ans: (c)

17. A software that allows a personal computer to pretend as a computer terminal is
a) terminal adapter
b) bulletin board
c) modem
d) terminal emulation
Ans: (d)


18. Find the output of the following program
int *p,*q;
p=(int *)1000;
q=(int *)2000;
printf("%d",(q-p));
Ans: 500

19. Which addressing mode is used in the following statements:
(a) MVI  B,55
(b) MOV B,A
(c) MOV M,A
Ans. (a) Immediate addressing mode.
(b) Register Addressing Mode
(c) Direct addressing mode

20. RS-232C standard is used in _____________.
Ans. Serial I/O

21. Memory. Management in Operating Systems is done by
a) Memory Management Unit
b) Memory management software of the Operating System
c) Kernel
Ans: (b)

22. What is done for a Push opertion?
Ans: SP is decremented and then the value is stored.


23. Binary equivalent of 52
Ans. 110100

24. Hexadecimal equivalent of 3452
Ans. 72A

25. Explain Just In Time Concept ?
Ans. Elimination of waste by purchasing manufacturing exactly when needed

26. A good way of unit testing s/w program is
Ans. User test

27. OOT uses
Ans. Encapsulated of detect methods

28.EDI useful in
Ans. Electronic Transmission

29. MRPII different from MRP
Ans. Modular version of man redundant initials

30. Hard disk time for R/W head to move to correct sector
Ans. Latency Time

31. The percentage of times a page number bound in associate register is called
Ans. Bit ratio

32. Expand MODEM
Ans. Modulator and Demodulator

33. RDBMS file system can be defined as
Ans. Interrelated

34. Super Key is
Ans. Primary key and Attribute

35. Windows 95 supports
(a) Multiuser
(b) n tasks
(c) Both
(d) None
Ans. (a)

36.In the command scanf, h is used for
Ans. Short int

37.A process is defined as
Ans. Program in execution

38.A thread is
Ans. Detachable unit of executable code)

39.What is the advantage of Win NT over Win 95
Ans. Robust and secure

40.How is memory management done in Win95
Ans. Through paging and segmentation

41.What is meant by polymorphism
Ans. Redfinition of a base class method in a derived class


42.What is the essential feature of inheritance
Ans. All properties of existing class are derived

43.What does the protocol FTP do
Ans. Transfer a file b/w stations with user authentification

44.In the transport layer ,TCP is what type of protocol
Ans. Connection oriented

45.Why is a gateway used
Ans. To connect incompatible networks

46.How is linked list implemented
Ans. By referential structures

47.What method is used in Win95 in multitasking
Ans. Non preemptive check

48.What is a semaphore
Ans. A method synchronization of multiple processes

49.What is the precedence order from high to low, of the symbols () ++ /
Ans. () , ++, /

50.Preorder of A*(B+C)/D-G
Ans.*+ABC/-DG

51.What is the efficiency of merge sort
Ans. O (n log n)

52.In which layer are routers used
Ans. In network layer

53.Which of the following sorting algorithm has average sorting behavior --
 Bubble sort, merge sort, heap sort, exchange sort
Ans Heap sort

54.In binary search tree which traversal is used for getting ascending order values—Inorder, post order, preorder
Ans. Inorder

55.What are device drivers used for
Ans. To provide software for enabling the hardware

56.What is fork command in unix
Ans. System call used to create process

57.What is make command in unix
Ans. Used for creation of more than one file

58.In unix. profile contains
Ans. Start up program

59.In unix ' ls 'stores contents in
Ans. node block

60. Which of the following involves context switch,
(a)  system call
(b)  privileged instruction
(c)  floating point exception
(d)  all the above
(e)  none of the above
Ans: (a)

61. In OST, terminal emulation is done in
(a) sessions layer
(b) application layer
(c) presentation layer
(d) transport layer
Ans: (b)


62. For 1 MB memory, the number of address lines required,
(a)11
(b)16
(c)22
(d)24
Ans. (b)


63. Semaphore is used for
(a) synchronization
(b) dead-lock avoidance
(c) box
(d) none
Ans. (a)


64. Which holds true for the following statement
     class c: public A, public B
a) 2 member in class A, B should not have same name
b) 2 member in class A, C should not have same name
c) both
d) none
Ans. (a)


65.Preproconia.. does not do which one of the following
(a) macro
(b) conditional complication
(c) in type checking
(d) including load file
Ans. (c)

66. Piggy backing is a technique for
a) Flow control
b) Sequence
c) Acknowledgement
d) retransmission
Ans. (c)

67. Which is not a memory management scheme?
a) Buddy system
b) swapping
c) monitors
d) paging
Ans : c


68. There was a circuit given using three nand gates with two inputs and one output.
    Find the output.
a) OR
b) AND
c) XOR
d) NOT
Ans. (a)

69. Integrated check value (ICV) are used as:
Ans. The client computes the ICV and then compares it with the senders value.


70. When applets are downloaded from web sites , a byte verifier performs _________?
Ans. Status check.

71. An IP/IPX packet received by a computer using... having IP/IPX  both how the packet is handled.
Ans. Read the, field in the packet header with to send IP or IPX protocol.


72. The UNIX shell ....
a) does not come with the rest of the system
b) forms the interface between the user and the kernal
c) does not give any scope for programming
d) deos not allow calling one program from with in another
e) all of the above
Ans. (b)


73. In UNIX a files i-node ......?
Ans. Is a data structure that defines all specifications of a file like the file size,
        number of lines to a file, permissions etc.


74. The very first process created by the kernel that runs till the kernel process is halts is
a) Init
b) getty
c) both (a) and (b)
d) none of these
Ans. (a)


75. In the process table entry for the kernel process, the process id value is
(a) 0
(b) 1
(c) 2
(d) 255
(e) it does not have a process table entry
Ans. (a)

76. Which of the following API is used to hide a window
a) Show Window
b) Enable Window
c) Move Window
d) SetWindowPlacement
e) None of the above
Ans. (a)


77. Which function is the entry point for a DLL in MS Windows 3.1
a) Main
b) Winmain
c) Dllmain
d) Libmain
e) None
Ans. (b)


78. The standard source for standard input, standard output and standard error is
a) the terminal
b) /dev/null
c) /usr/you/input, /usr/you/output/, /usr/you/error respectively
d) None
Ans. (a)


79. The redirection operators > and >>
a) do the same function
b) differ : > overwrites, while >> appends
c) differ : > is used for input while >> is used for output
d) differ : > write to any file while >> write only to standard output
e) None of these
Ans. (b)


80. The command grep first second third /usr/you/myfile
a) prints lines containing the words first, second or third from the file /usr/you/myfile
b) searches for lines containing the pattern first in the files
second, third, and /usr/you/myfile and prints them
c) searches the files /usr/you/myfile and third for lines containing the words first or second and prints them
d) replaces the word first with the word second in the files third and /usr/you/myfile
e) None of the above
Ans. (b)


81. You are creating a Index on EMPNO column in the EMPLOYEE table. Which statement will you use?
a) CREATE INdEX emp_empno_idx ON employee, empno;
b) CREATE INdEX emp_empno_idx FOR employee, empno;
c) CREATE INdEX emp_empno_idx ON employee(empno);
d) CREATE emp_empno_idx INdEX ON employee(empno);
Ans. c

82. Which program construct must return a value?
a) Package
b) Function
c) Anonymous block
d) Stored Procedure
e) Application Procedure
Ans. b

83. Which Statement would you use to remove the EMPLOYEE_Id_PK PRIMARY KEY constraint and all depending constraints from the EMPLOYEE table?
a) ALTER TABLE employee dROP PRIMARY KEY CASCAdE;
b) ALTER TABLE employee dELETE PRIMARY KEY CASCAdE;
c) MOdIFY TABLE employee dROP CONSTRAINT employee_id_pk CASCAdE;
d) ALTER TABLE employee dROP PRIMARY KEY employee_id_pk CASCAdE;
e) MOdIFY TABLE employee dELETE PRIMARY KEY employee_id_pk CASCAdE;
Ans. a

84. Which three commands cause a transaction to end? (Choose three)
a) ALTER
b) GRANT
c) DELETE
d) INSERT
e) Update
f) ROLLBACK
Ans. a ,b ,f
85. Under which circumstance should you create an index on a table?
a) The table is small.
b) The table is updated frequently.
c) A columns values are static and contain a narrow range of values
d) Two columns are consistently used in the WHERE clause join condition of SELECT
     statements.

Ans.d

86. What was the first name given to Java Programming Language.

a) Oak - Java
b) Small Talk
c) Oak
d) None
Ans.a

87.When a bicycle is in motion,the force of friction exerted by the ground on the two wheels is such that it acts

(a) In the backward direction on the front wheel and in the forward direction on the rear wheel.

(b) In the forward direction on the front wheel and in the backward direction on the rear wheel.

(c) In the backward direction on both the front and rear wheels.
(d) In the backward direction on both the front and rear wheels.

Ans. (d)

88. A certain radioactive element A, has a half life = t seconds.
    In (t/2) seconds the fraction of the initial quantity of the element so far decayed is nearly

(a) 29%
(b) 15%
(c) 10%
(d) 45%

Ans. (a)

89. Which of the following plots would be a straight line ?

(a) Logarithm of decay rate against logarithm of time
(b) Logarithm of decay rate against logarithm of number of decaying nuclei
(c) Decay rate against time
(d) Number of decaying nuclei against time

Ans. (b)

90. A radioactive element x has an atomic number of 100.
    It decays directly into an element y which decays directly into element z.
    In both processes a charged particle is emitted.
    Which of the following statements would be true?

(a) y has an atomic number of 102
(b) y has an atomic number of 101
(c) z has an atomic number of 100
(d) z has an atomic number of 101

Ans. (b)

91. If the sum of the roots of the equation ax² + bx + c=0 is equal to the sum of the squares of their reciprocals
    then a/c, b/a, c/b are in

(a) AP
(b) GP
(c) HP
(d) None of these

Ans. (c)

92. A man speaks the truth 3 out of 4 times.
    He throws a die and reports it to be a 6.
    What is the probability of it being a 6?

(a) 3/8
(b) 5/8
(c) 3/4
(d) None of the above

Ans. (a)

93. If cos²A + cos²B + cos²C = 1 then ABC is a

(a) Right angle triangle
(b) Equilateral triangle
(c) All the angles are acute
(d) None of these

Ans. (a)

94. Image of point (3,8) in the line  x + 3y = 7 is

(a) (-1,-4)
(b) (-1,4)
(c) (2,-4)
(d) (-2,-4)

Ans. (a)

95. The mass number of a nucleus is

(a) Always less than its atomic number
(b) Always more than its atomic number
(c) Sometimes more than and sometimes equal to its atomic number
(d) None of the above

Ans. (c)

96. The maximum KE of the photoelectron emitted from a surface is dependent on

(a) The intensity of incident radiation
(b) The potential of the collector electrode
(c) The frequency of incident radiation
(d) The angle of incidence of radiation of the surface

Ans. (c)

97. Which of the following is not an essential condition for interference

(a) The two interfering waves must be propagated in almost the same direction or
     the two interfering waves must intersect at a very small angle
(b) The waves must have the same time period and wavelength
(c) Amplitude of the two waves should be the same
(d) The interfering beams of light must originate from the same source

Ans. (c)

98. When X-Ray photons collide with electrons

(a) They slow down
(b) Their mass increases
(c) Their wave length increases
(d) Their energy decreases

Ans. (c)

99. An electron emits energy

(a) Because its in orbit
(b) When it jumps from one energy level to another
(c) Electrons are attracted towards the nucleus
(d) The electrostatic force is insufficient to hold the electrons in orbits

Ans. (b)

100. How many bonds are present in CO₂ molecule?

(a) 1
(b) 2
(c) 0
(d) 4

Ans. (d)

C, C++ Tech Aptitude Questions

1. What is a modifier?
Answer:
A modifier, also called a modifying function is a member function that changes the value of at least one data member. In other words, an operation that modifies the state of an object. Modifiers are also known as ‘mutators’.

2. What is an accessor?
Answer:
An accessor is a class operation that does not modify the state of an object. The accessor functions need to be declared as const operations .

3. Differentiate between a template class and class template.
Answer:
Template class:
A generic definition or a parameterized class not instantiated until the client provides the needed information. It’s jargon for plain templates.
Class template:
A class template specifies how individual classes can be constructed much like the way a class specifies how individual objects can be constructed. It’s jargon for plain classes.

4. When does a name clash occur?
Answer:
A name clash occurs when a name is defined in more than one place. For example., two different class libraries could give two different classes the same name. If you try to use many class libraries at the same time, there is a fair chance that you will be unable to compile or link the program because of name clashes.

5. Define namespace.
Answer:
It is a feature in c++ to minimize name collisions in the global name space. This namespace keyword assigns a distinct name to a library that allows other libraries to use the same identifier names without creating any name collisions. Furthermore, the compiler uses the namespace signature for differentiating the definitions.

6. What is the use of ‘using’ declaration.
Answer:
A using declaration makes it possible to use a name from a namespace without the scope operator.

7. What is an Iterator class?
Answer:
A class that is used to traverse through the objects maintained by a container class. There are five categories of iterators:
 input iterators,
 output iterators,

 forward iterators,
 bidirectional iterators,
 random access.
An iterator is an entity that gives access to the contents of a container object without violating encapsulation constraints. Access to the contents is granted on a one-at a-time basis in order. The order can be storage order (as in lists and queues) or some arbitrary order (as in array indices) or according to some ordering relation (as in an ordered binary tree). The iterator is a construct, which provides an interface that, when called, yields either the next element in the container, or some value denoting the fact that there are no more elements to examine. Iterators hide the details of access to and update of the elements of a container class. The simplest and safest iterators are those that permit read-only access to the contents of a container class. The following code fragment shows how an iterator might appear in code:
cont_iter:=new cont_iterator();
x:=cont_iter.next();
while x/=none do
...
s(x);
...
x:=cont_iter.next();
end;

In this example, cont_iter is the name of the iterator. It is created on the first line by instantiation of cont_iterator class, an iterator class defined to iterate over some container class, cont. Succesive elements from the container are carried to x. The loop terminates when x is bound to some empty value. (Here, none)In the middle of the loop, there is s(x) an operation on x, the current element from the container. The next element of the container is obtained at the bottom of the loop.

9. List out some of the OODBMS available.
Answer:
 GEMSTONE/OPAL of Gemstone systems.
 ONTOS of Ontos.
 Objectivity of Objectivity inc.
 Versant of Versant object technology.
 Object store of Object Design.
 ARDENT of ARDENT software.
 POET of POET software.

10. List out some of the object-oriented methodologies.
Answer:
 Object Oriented Development (OOD) (Booch 1991,1994).
 Object Oriented Analysis and Design (OOA/D) (Coad and Yourdon 1991).
 Object Modelling Techniques (OMT) (Rumbaugh 1991).
 Object Oriented Software Engineering (Objectory) (Jacobson 1992).
 Object Oriented Analysis (OOA) (Shlaer and Mellor 1992).

11. What is an incomplete type?
Answer:
Incomplete types refers to pointers in which there is non availability of the implementation of the referenced location or it points to some location whose value is not available for modification.
Example:
int *i=0x400 // i points to address 400
*i=0; //set the value of memory location pointed by i.
Incomplete types are otherwise called uninitialized pointers.

12. What is a dangling pointer?
Answer:
A dangling pointer arises when you use the address of an object after its lifetime is over. This may occur in situations like returning addresses of the automatic variables from a function or using the address of the memory block after it is freed.

13. Differentiate between the message and method.
Answer:
Objects communicate by sending messages Provides response to a message to each other.
A message is sent to invoke a method. It is an implementation of an operation.

14. What is an adaptor class or Wrapper class?
Answer:
A class that has no functionality of its own. Its member functions hide the use of a third party software component or an object with the non-compatible interface or a nonobject- oriented implementation.

15. What is a Null object?
Answer:
It is an object of some class whose purpose is to indicate that a real object of that class does not exist. One common use for a null object is a return value from a member function that is supposed to return an object with some specified properties but cannot find such an object.

16. What is class invariant?
Answer:
A class invariant is a condition that defines all valid states for an object. It is a logical condition to ensure the correct working of a class. Class invariants must hold when an object is created, and they must be preserved under all operations of the class. In particular all class invariants are both preconditions and post-conditions for all operations or member functions of the class.

17. What do you mean by Stack unwinding?
Answer:
It is a process during exception handling when the destructor is called for all local objects between the place where the exception was thrown and where it is caught. 18. Define precondition and post-condition to a member function.

Answer:
Precondition:
A precondition is a condition that must be true on entry to a member function. A class is used correctly if preconditions are never false. An operation is not responsible for doing anything sensible if its precondition fails to hold. For example, the interface invariants of stack class say nothing about pushing yet another element on a stack that is already full. We say that isful() is a precondition of the push operation.
Post-condition:
A post-condition is a condition that must be true on exit from a member function if the precondition was valid on entry to that function. A class is implemented correctly if post-conditions are never false. For example, after pushing an element on the stack, we know that isempty() must necessarily hold. This is a post-condition of the push operation.

19. What are the conditions that have to be met for a condition to be an invariant of the
class?
Answer:
 The condition should hold at the end of every constructor.
 The condition should hold at the end of every mutator(non-const) operation.

20. What are proxy objects?
Answer:
Objects that stand for other objects are called proxy objects or surrogates.
Example:
template
class Array2D
{
public:
class Array1D
{
public:
T& operator[] (int index);
const T& operator[] (int index) const;
...
};
Array1D operator[] (int index);
const Array1D operator[] (int index) const;
...
};
The following then becomes legal:
Array2Ddata(10,20);
........
cout<Here data[3] yields an Array1D object and the operator [] invocation on that object yields the float in position(3,6) of the original two dimensional array. Clients of the Array2D class need not be aware of the presence of the Array1D class. Objects of this latter class stand for one-dimensional array objects that, conceptually, do not exist for lients of Array2D. Such clients program as if they were using real, live, two-dimensional arrays. Each Array1D object stands for a one-dimensional array that is absent from a conceptual model used by the clients of Array2D. In the above example, Array1D is a proxy class. Its instances stand for one-dimensional arrays that, conceptually, do not exist

21. Name some pure object oriented languages.
Answer:
 Smalltalk,
 Java,
 Eiffel,
 Sather.

22. Name the operators that cannot be overloaded.
Answer:
sizeof . .* .-> :: ?:

23. What is a node class?
Answer:
A node class is a class that,
 relies on the base class for services and implementation,
 provides a wider interface to te users than its base class,
 relies primarily on virtual functions in its public interface
 depends on all its direct and indirect base class
 can be understood only in the context of the base class
 can be used as base for further derivation
 can be used to create objects.
A node class is a class that has added new services or functionality beyond the services inherited from its base class.

24. What is an orthogonal base class?
Answer:
If two base classes have no overlapping methods or data they are said to be independent of, or orthogonal to each other. Orthogonal in the sense means that two classes operate in different dimensions and do not interfere with each other in any way. The same derived class may inherit such classes with no difficulty.

25. What is a container class? What are the types of container classes?
Answer:
A container class is a class that is used to hold objects in memory or external storage. A container class acts as a generic holder. A container class has a predefined ehavior and a well-known interface. A container class is a supporting class whose purpose is to hide the topology used for maintaining the list of objects in memory. When a container class contains a group of mixed objects, the container is called a heterogeneous container; when the container is holding a group of objects that are all the same, the container is called a homogeneous container.

26. What is a protocol class?
Answer:
An abstract class is a protocol class if:
 it neither contains nor inherits from classes that contain member data, non-virtual functions, or private (or protected) members of any kind.
 it has a non-inline virtual destructor defined with an empty implementation,
 all member functions other than the destructor including inherited functions, are declared pure virtual functions and left undefined.

27. What is a mixin class?
Answer:
A class that provides some but not all of the implementation for a virtual base class is often called mixin. Derivation done just for the purpose of redefining the virtual functions in the base classes is often called mixin inheritance. Mixin classes typically don't share common bases.

28. What is a concrete class?
Answer:
A concrete class is used to define a useful object that can be instantiated as an automatic variable on the program stack. The implementation of a concrete class is defined. The concrete class is not intended to be a base class and no attempt to minimize dependency on other classes in the implementation or behavior of the class.

29.What is the handle class?
Answer:
A handle is a class that maintains a pointer to an object that is programmatically accessible through the public interface of the handle class.
Explanation:
In case of abstract classes, unless one manipulates the objects of these classesthrough pointers and references, the benefits of the virtual functions are lost. User code may become dependent on details of implementation classes because an abstract type cannot be allocated statistically or on the stack without its size being known. Using pointers or references implies that the burden of memory management falls on the user. Another limitation of abstract class object is of fixed size. Classes however are used to represent concepts that require varying amounts of storage to implement them. A popular technique for dealing with these issues is to separate what is used as a single object in two parts: a handle providing the user interface and a representation holding all
or most of the object's state. The connection between the handle and the representation is typically a pointer in the handle. Often, handles have a bit more data than the simple epresentation pointer, but not much more. Hence the layout of the handle is typically table, even when the representation changes and also that handles are small enough to move around relatively freely so that the user needn’t use the pointers and the references.

30. What is an action class?
Answer:
The simplest and most obvious way to specify an action in C++ is to write a
function. However, if the action has to be delayed, has to be transmitted 'elsewhere'
before being performed, requires its own data, has to be combined with other actions, etc
then it often becomes attractive to provide the action in the form of a class that can
execute the desired action and provide other services as well. Manipulators used with
iostreams is an obvious example.
Explanation:
A common form of action class is a simple class containing just one virtual
function.
class Action
{
public:
virtual int do_it( int )=0;
virtual ~Action( );
}
Given this, we can write code say a member that can store actions for later
execution without using pointers to functions, without knowing anything about the
objects involved, and without even knowing the name of the operation it invokes. For
example:
class write_file : public Action
{
File& f;
public:
int do_it(int)
{
return fwrite( ).suceed( );
}
};
class error_message: public Action
{
response_box db(message.cstr( ),"Continue","Cancel","Retry");
switch (db.getresponse( ))
{
case 0: return 0;

case 1: abort();
case 2: current_operation.redo( );return 1;
}
};
A user of the Action class will be completely isolated from any knowledge of
derived classes such as write_file and error_message.

100 Technical Questions with answers

Technical Questions

1. A 2MB PCM(pulse code modulation) has
a) 32 channels
b) 30 voice channels & 1 signalling channel.
c) 31 voice channels & 1 signalling channel.
d) 32 channels out of which 30 voice channels, 1 signalling channel, & 1 Synchronizatio channel.
Ans: (c)

2. Time taken for 1 satellite hop in voice communication is
a) 1/2 second
b) 1 seconds
c) 4 seconds
d) 2 seconds
Ans: (a)

3. Max number of satellite hops allowed in voice communication is :
a) only one
b) more han one
c) two hops
d) four hops
Ans: (c)

4. What is the max. decimal number that can be accomodated in a byte.
a) 128
b) 256
c) 255
d) 512
Ans: (c)

5. Conditional results after execution of an instruction in a micro processor is stored in
a) register
b) accumulator
c) flag register
d) flag register part of PSW(Program Status Word)
Ans: (d)

6. Frequency at which VOICE is sampled is
a) 4 Khz
b) 8 Khz
c) 16 Khz
d) 64 Khz
Ans: (a)

7. Line of Sight is
a) Straight Line
b) Parabolic
c) Tx & Rx should be visible to each other
d) none
Ans: (c)

8. Purpose of PC(Program Counter) in a MicroProcessor is
a) To store address of TOS(Top Of Stack)
b) To store address of next instruction to be executed.
c) count the number of instructions.
d) to store base address of the stack.
Ans: (b)

9. What action is taken when the processor under execution is interrupted by a non-maskable interrupt?
a) Processor serves the interrupt request after completing the execution of the current instruction.
b) Processor serves the interupt request after completing the current task.
c) Processor serves the interupt request immediately.
d) Processor serving the interrupt request depends upon the priority of the current task under execution.
Ans: (a)

10. The status of the Kernel is
a) task
b) process
c) not defined.
d) none of the above.
Ans: (b)

11. To send a data packet using datagram , connection will be established
a) before data transmission.
b) connection is not established before data transmission.
c) no connection is required.
d) none of the above.
Ans: (c)

12. Word allignment is
a) alligning the address to the next word boundary of the machine.
b) alligning to even boundary.
c) alligning to word boundary.
d) none of the above.
Ans: (a)

13 When a 'C' function call is made, the order in which parameters passed to the function are pushed into the stack is
a) left to right
b) right to left
c) bigger variables are moved first than the smaller variales.
d) smaller variables are moved first than the bigger ones.e) none of the above.
Ans: (b)

14 What is the type of signalling used between two exchanges?
a) inband
b) common channel signalling
c) any of the above
d) none of the above.
Ans: (a)

15 Buffering is
a) the process of temporarily storing the data to allow for small variation in device speeds
b) a method to reduce cross talks
c) storage of data within transmitting medium until the receiver is ready to receive.
d) a method to reduce routing overhead.
Ans: (a)

16. Memory allocation of variables declared in a program is
a) allocated in RAM
b) allocated in ROM.
c) allocated on stack.
d) assigned to registers.
Ans: (c)

17. A software that allows a personal computer to pretend as a computer terminal is
a) terminal adapter
b) bulletin board
c) modem
d) terminal emulation
Ans: (d)

18. Find the output of the following program
int *p,*q;
p=(int *)1000;
q=(int *)2000;
printf("%d",(q-p));
Ans: 500

19. Which addressing mode is used in the following statements:
(a) MVI B,55 (b) MOV B,A (c) MOV M,A
Ans. (a) Immediate addressing mode.
(b) Register Addressing Mode
(c) Direct addressing mode

20. RS-232C standard is used in _____________.
Ans. Serial I/O

21. Memory. Management in Operating Systems is done by
a) Memory Management Unit
b) Memory management software of the Operating System
c) Kernel
Ans: (b)

22. What is done for a Push opertion?
Ans: SP is decremented and then the value is stored.

23. Binary equivalent of 52
Ans. 110100

24. Hexadecimal equivalent of 3452
Ans. 72A

25. Explain Just In Time Concept ?
Ans. Elimination of waste by purchasing manufacturing exactly when needed

26. A good way of unit testing s/w program is
Ans. User test

27. OOT uses
Ans. Encapsulated of detect methods

28.EDI useful in
Ans. Electronic Transmission

29. MRPII different from MRP
Ans. Modular version of man redundant initials

30. Hard disk time for R/W head to move to correct sector
Ans. Latency Time

31. The percentage of times a page number bound in associate register is called
Ans. Bit ratio

32. Expand MODEM
Ans. Modulator and Demodulator

33. RDBMS file system can be defined as
Ans. Interrelated

34. Super Key is
Ans. Primary key and Attribute

35. Windows 95 supports
(a) Multiuser
(b) n tasks
(c) Both
(d) None
Ans. (a)

36.In the command scanf, h is used for
Ans. Short int

37.A process is defined as
Ans. Program in execution

38.A thread is
Ans. Detachable unit of executable code

39.What is the advantage of Win NT over Win 95
Ans. Robust and secure


40.How is memory management done in Win95
Ans. Through paging and segmentation

41.What is meant by polymorphism
Ans. Redfinition of a base class method in a derived class

42.What is the essential feature of inheritance
Ans. All properties of existing class are derived

43.What does the protocol FTP do
Ans. Transfer a file b/w stations with user authentification

44.In the transport layer ,TCP is what type of protocol
Ans. Connection oriented

45.Why is a gateway used
Ans. To connect incompatible networks

46.How is linked list implemented
Ans. By referential structures

47.What method is used in Win95 in multitasking
Ans. Non preemptive check

48.What is a semaphore
Ans. A method synchronization of multiple processes

49.What is the precedence order from high to low, of the symbols () ++ /
Ans. () , ++, /


50.Preorder of A*(B+C)/D-G
Ans.*+ABC/-DG

51.What is the efficiency of merge sort
Ans. O (n log n)

52.In which layer are routers used
Ans. In network layer

53.Which of the following sorting algorithm has average sorting behavior -- Bubble sort, merge sort, heap sort, exchange sort
Ans. Heap sort

54.In binary search tree which traversal is used for getting ascending order values—Inorder, post order, preorder
Ans. Inorder

55.What are device drivers used for
Ans. To provide software for enabling the hardware

56.What is fork command in unix
Ans. System call used to create process

57.What is make command in unix
Ans. Used for creation of more than one file

58.In unix. profile contains
Ans. Start up program

59.In unix ' ls 'stores contents in
Ans. node block

60. Which of the following involves context switch,
(a) system call
(b) privileged instruction
(c) floating point exception
(d) all the above
(e) none of the above
Ans: (a)

61. In OST, terminal emulation is done in
(a) sessions layer
(b) application layer
(c) presentation layer
(d) transport layer
Ans: (b)

62. For 1 MB memory, the number of address lines required,
(a)11
(b)16
(c)22
(d)24
Ans. (b)

63. Semaphore is used for
(a) synchronization
(b) dead-lock avoidance
(c) box
(d) none
Ans. (a)

64. Which holds true for the following statement
class c: public A, public B
a) 2 member in class A, B should not have same name
b) 2 member in class A, C should not have same name
c) both
d) none
Ans. (a)

65.Preproconia.. does not do which one of the following
(a) macro
(b) conditional complication
(c) in type checking
(d) including load file
Ans. (c)

66. Piggy backing is a technique for
a) Flow control
b) Sequence
c) Acknowledgement
d) retransmission
Ans. (c)

67. Which is not a memory management scheme?
a) Buddy system
b) swapping
c) monitors
d) paging
Ans : c

68. There was a circuit given using three nand gates with two inputs and one output. Find the output.
a) OR
b) AND
c) XOR
d) NOT
Ans. (a)

69. Integrated check value (ICV) are used as:
Ans. The client computes the ICV and then compares it with the senders value.

70. When applets are downloaded from web sites , a byte verifier performs _________?
Ans. Status check.

71. An IP/IPX packet received by a computer using... having IP/IPX both how the packet is handled.
Ans. Read the, field in the packet header with to send IP or IPX protocol.

72. The UNIX shell ....
a) does not come with the rest of the systemb) forms the interface between the user and the kernalc) does not give any scope for programmingd) deos not allow calling one program from with in anothere) all of the above
Ans. (b)

73. In UNIX a files i-node ......?
Ans. Is a data structure that defines all specifications of a file like the file size, number of lines to a file, permissions etc.

74. The very first process created by the kernel that runs till the kernel process is halts is
a) Init
b) getty
c) both (a) and (b)
d) none of these
Ans. (a)

75. In the process table entry for the kernel process, the process id value is
(a) 0
(b) 1
(c) 2
(d) 255
(e) it does not have a process table entry
Ans. (a)

76. Which of the following API is used to hide a window
a) Show Window
b) Enable Window
c) Move Window
d) SetWindowPlacement
e) None of the above
Ans. (a)

77. Which function is the entry point for a DLL in MS Windows 3.1
a) Main
b) Winmain
c) Dllmain
d) Libmain
e) None
Ans. (b)

78. The standard source for standard input, standard output and standard error is
a) the terminal
b) /dev/null
c) /usr/you/input, /usr/you/output/, /usr/you/error respectively
d) None
Ans. (a)

79. The redirection operators > and >>
a) do the same function
b) differ : > overwrites, while >> appends
c) differ : > is used for input while >> is used for output
d) differ : > write to any file while >> write only to standard output
e) None of these
Ans. (b)

80. The command grep first second third /usr/you/myfile
a) prints lines containing the words first, second or third from the file /usr/you/myfile
b) searches for lines containing the pattern first in the filessecond, third, and /usr/you/myfile and prints them
c) searches the files /usr/you/myfile and third for lines containing the words first or second and prints them
d) replaces the word first with the word second in the files third and /usr/you/myfile
e) None of the above
Ans. (b)

81. You are creating a Index on EMPNO column in the EMPLOYEE table. Which statement will you use?
a) CREATE INdEX emp_empno_idx ON employee, empno;
b) CREATE INdEX emp_empno_idx FOR employee, empno;
c) CREATE INdEX emp_empno_idx ON employee(empno);
d) CREATE emp_empno_idx INdEX ON employee(empno);
Ans. c

82. Which program construct must return a value?
a) Package
b) Function
c) Anonymous block
d) Stored Proceduree) Application Procedure
Ans. b

83. Which Statement would you use to remove the EMPLOYEE_Id_PK PRIMARY KEY constraint and all depending constraints from the EMPLOYEE table?a
) ALTER TABLE employee dROP PRIMARY KEY CASCAdE;
b) ALTER TABLE employee dELETE PRIMARY KEY CASCAdE;
c) MOdIFY TABLE employee dROP CONSTRAINT employee_id_pk CASCAdE;
d) ALTER TABLE employee dROP PRIMARY KEY employee_id_pk CASCAdE;
e) MOdIFY TABLE employee dELETE PRIMARY KEY employee_id_pk CASCAdE;
Ans. a

84. Which three commands cause a transaction to end? (Choose three)
a) ALTER
b) GRANT c
) DELETE
d) INSERT
e) Updatef) ROLLBACK
Ans. a ,b ,f

85. Under which circumstance should you create an index on a table?
a) The table is small.
b) The table is updated frequently.
c) A columns values are static and contain a narrow range of values
d) Two columns are consistently used in the WHERE clause join condition of SELECT statements.
Ans.d

86. What was the first name given to Java Programming Language.
a) Oak - Java
b) Small Talk
c) Oak
d) None
Ans.a

87.When a bicycle is in motion,the force of friction exerted by the ground on the two wheels is such that it acts
(a) In the backward direction on the front wheel and in the forward direction on the rear wheel.
(b) In the forward direction on the front wheel and in the backward direction on the rear wheel.
(c) In the backward direction on both the front and rear wheels.
(d) In the backward direction on both the front and rear wheels.
Ans. (d)

88. A certain radioactive element A, has a half life = t seconds. In (t/2) seconds the fraction of the initial quantity of the element so far decayed is nearly
(a) 29%
(b) 15%
(c) 10%
(d) 45%
Ans. (a)

89. Which of the following plots would be a straight line ?
(a) Logarithm of decay rate against logarithm of time
(b) Logarithm of decay rate against logarithm of number of decaying nuclei
(c) Decay rate against time
(d) Number of decaying nuclei against time
Ans. (b)

90. A radioactive element x has an atomic number of 100. It decays directly into an element y which decays directly into element z. In both processes a charged particle is emitted. Which of the following statements would be true?
(a) y has an atomic number of 102
(b) y has an atomic number of 101
(c) z has an atomic number of 100
(d) z has an atomic number of 101
Ans. (b)

91. If the sum of the roots of the equation ax2 + bx + c=0 is equal to the sum of the squares of their reciprocals then a/c, b/a, c/b are in
(a) AP
(b) GP
(c) HP
(d) None of these
Ans. (c)

92. A man speaks the truth 3 out of 4 times. He throws a die and reports it to be a 6. What is the probability of it being a 6?
(a) 3/8
(b) 5/8
(c) 3/4
(d) None of the above
Ans. (a)

93. If cos2A + cos2B + cos2C = 1 then ABC is a
(a) Right angle triangle
(b) Equilateral triangle
(c) All the angles are acute
(d) None of these
Ans. (a)

94. Image of point (3,8) in the line x + 3y = 7 is
(a) (-1,-4)
(b) (-1,4)
(c) (2,-4)
(d) (-2,-4)
Ans. (a)

95. The mass number of a nucleus is
(a) Always less than its atomic number
(b) Always more than its atomic number
(c) Sometimes more than and sometimes equal to its atomic number
(d) None of the above
Ans. (c)

96. The maximum KE of the photoelectron emitted from a surface is dependent on
(a) The intensity of incident radiation
(b) The potential of the collector electrode
(c) The frequency of incident radiation
(d) The angle of incidence of radiation of the surface
Ans. (c)

97. Which of the following is not an essential condition for interference
(a) The two interfering waves must be propagated in almost the same direction or the two interfering waves must intersect at a very small angle
(b) The waves must have the same time period and wavelength
(c) Amplitude of the two waves should be the same
(d) The interfering beams of light must originate from the same source
Ans. (c)

98. When X-Ray photons collide with electrons
(a) They slow down
(b) Their mass increases
(c) Their wave length increases
(d) Their energy decreases
Ans. (c)

99. An electron emits energy
(a) Because its in orbit
(b) When it jumps from one energy level to another
(c) Electrons are attracted towards the nucleus
(d) The electrostatic force is insufficient to hold the electrons in orbits
Ans. (b)

100. How many bonds are present in CO2 (Carbon di Oxide) molecule?
(a) 1
(b) 2
(c) 0
(d) 4
Ans. (d)

Aptitude Papers with solutions

1. A shopkeeper arranges his fruits in such a way that putting say either 3,or 9,or 7 apples in a row each time one apple is left. but when he puts say 11 apples in a row no apple is left.find no. of apples.

ans: take l.c.m. of earlier three nos. add 1 if divided by 11 fine else multiply by 2 add 1 divide by 11 .if not divisible keep on repeating.

2. A problem of staircase:if i start going down, having gone down 4 steps i see x coming up.i meet x in way going down.when i had still 7 steps to go down x had gone up .find no. of steps in the staircase.condition: for each of my one step down x goes up 2 steps.ans:22

solution:say total no. of steps x2(x-11)==xx="

3. Problem of merrygoround.tom on a merrygoround finds that one third of people ahead of him and three fourth of people behind him is equal to the no. of people on the merrygoround.find the no. of people on the merrygoround.

ans:13since merry gorund is circular so 3/4x+1/3x==x+1.

4. A problem of cards .four persons sitting on a table.infront of each one of them one card is lying not having same colours on both sides.2 blue,2 red,2 green faces. each one guesses the color of unseen face of card .(guesses i don’t remember) exactly 2 are lying.the front faces of card are red,blue,green,red respectively.find the colors of unseen faces of card.

5. five persons in a conference.a & b can communicate in english.when d joins the only coomon language of communication is spanish. a ,b,e can talk to each other in french only.exactly 3 people know portugese. the number of languages known by different persons are 1,2,3,4,5. some other similar conditions . you have to find answers to four questions based n these facts.

6. say ona sacle of 100:85 have phones,80 cars,75 married,70 have houses. how many minimum persons are married,have phone car and houses on a scale of 100.

7. some series given3 10 20 27 54 61 _ans .162some other seriestrick: find suare root then add some number etc.

8. some conditions on xz etc.

9. afternoon temperatures of five days are recorded.each temperature is different.multiple is 12.

ans:-1,1,2,-2,3

Aptitude Question - Self Practice

Aptitude Questions

1. There r some bees in a garden..1/5th of them went to a particular flower,1/3rd went to another flower,3 times the difference of the above two went to third flower..n one was remaining n it was roamingaround..how many bees were there

Ans:15

2. Jim n Harry have the same number of marbles when they start playing..n then afterwards...Jim gains 20 marbles and later he loses 2/3rds of what he had..now Harry has 4 times as many marbles as Jimhas..What r the initial number of marbles that each of them had?Ans:100 each

3. F,G,H,J,K are some juniors and P,Q,R,S are some seniors...and there are 3 communities Cultural,Recreation n Ethics..n each contained 3 members each..n each one was a member of only one committee..

i)F,Q are in Cultural committee.

ii)P is in recreation committee.

iii)J wont be in a committee where H or Q are there.

iv)G will be in recreation committe if S also works in recreation committee.

v)there will be atleast one senior in each committee.

vi)R wont be in a committee is S is there In this 4 parts were there

They will give some conditions and ask you to choose from the options. Now form the own options that you can make by seeing the question so that you will be able to solve similar problems by yourselves.

4. There was a community in which there were 1000 couples.In that 2/3rd of men who r taller r also heavier n 3/4th of the men who r heavier r also taller n there were 120 women who were both heavier n taller than men.So how many men r both taller n heavier than men

5. A man drives with constant speed..n he after some time he sees a milestone with 2-digits..then he travels for an hr n sees the same 2 digits in reverse order..n then after an hr he sees that themilestone has the same 2 digits with a 0 between them..so whats the man speed?Ans:45km/hr

6. There were 2 systems A n B.14 degrees in A is equivalent to 36 in system B.and 133 in A is equivalent to 87 in B.now what is the temperature where they both r equal?

Ans:51.25 (conversion A=(7/3)B-70)

7. X Y Z X Y ZA B + A B -------- ----- ------------- C D E F B G A

find X,Y,Z,G

8. A women buys some shoestrips n then 4 times of that she buys packet pins n then 8 times of shoestrips she buys handkerchiefs..n she has a bill of Rs3.24..n she pays for each article as many paise as there r articles(of tht particular item).Now whats the number of handkerchiefs?

Ans:16

9. Ms.Anitha got her salary n she spent half of it in shopping n gave 1RS to a beggar.After that 1/2 of the remaining money she spends in a hotel n she gives Rs.2/- as a tip to waiter.n then 1/2 of the remaining she spends again n she gives 3 RS as charity..n after thatfinally she is left with Rs 1/- when she comes out.Whats the actual money she had?

Rs 42/-

10. There r 2 children..one of them lies on Monday,wednesday n friday n tell truth on every other day.the other will lie on Tuesday,thursday n saturday.n always tells truth on other days..n both of them tell the truth on sundays.. then which of the following can be deduced?

i)If its a sunday both will say so

ii)if one of then says a correct day then other will lie everything.

Aptitude paper with Answers

Aptitude Questions

1. A software engineer returns from America. As he is fat he decided to have evening walk.....he started at 3pm. he walks along the road at 4km/hr for some time then he climbs a upward slope area at 3km/hr then downwards at the rate of 6km/hr. then back to the home through the road at 4km/hr. what is the distance he covered in one way if he reaches back home at 9pm.

2. men and lodge related question a)1 man related to 2lodges.b)each lodge has 3 men.c)only 1 man common b/w 2 lodges

3. A child questions his father, "What is your father's age", to which the father answers "He was aged X in year X^2 (X square) ". If the context is 20th Century, What is his Date of Birth?

4. A man rides cycle for two third of the distance to be covered. then his tyre got punctured. he walks the rest of the distance and found he took twice the time for walking compared to riding. How fast he can ride compared to walk.

5. 51 teams are there and they are to play basketball matches. A team is out of the tournament if that looses 2 games. what is the maximum number of games to be played to decide one winner.

6. who was the murderer(of smith) roger,o'neil,wait the waiter poisened smith with which friend. each of the friends tells 3 stmts 1 of which is false (1 stmt of each friend is false)

7. Nalanda,Rampur, Triloknagar, Maninagar etc some conditions are given....then u have to find which has the population below 5 lakhs.. whic is not the capital 2 industrial towns,2 harbours,longitude relation,latitude relation......etc (four questions based on these)

8. Another one on A,B,C , D and E younger and older relation + occupation of each nutritionist, doctor,planner etc. find who is who ?

9. Two lamps sold for Rs.12 each profit of 25% on 1 and loss 0f 20% on other? did he gain or lose?by how much?

10. A,B,C are persons and thy r div into three groups: Sororrean [always truth] , Nororrean [always lie] and Midrorrean [alternate-but not in any order as they speak truth first of false first]--repaet from earlier papers.


Answers

1. Ans: 12 km (one way )( total distance:12* 2 = 24 km)
2. Ans: 6 men and 4lodges
3. Ans: 1892
4. Ans: V(riding)=4*V(walking)[4 times]
5. Ans:101 matches
6. Ans: Roger was the murderer.(not sure)
9. Ans:60 paise loss
10. Ans:A:midrorean B: nororrean C:sororrean

Aptitude Questions with answers

Aptitude Questions

1. One guy has Rs. 100/- in hand. He has to buy 100 balls. One football costs Rs. 15/, One Cricket ball costs Re. 1/- and one table tennis ball costs Rs. 0.25 He spend the whole Rs. 100/- to buy the balls. How many of each balls he bought?

2. The distance between Station Atena and Station Barcena is 90 miles. A train starts from Atena towards Barcena. A bird starts at the same time from Barcena straight towards the moving train. On reaching the train, it instantaneously turns back and returns to Barcena. The bird makes these journeys from Barcena to the train and back to Barcena continuously till the train reaches Barcena. The bird finally returns to Barcena and rests. Calculate the total distance in miles the bird travels in the following two cases: (a) The bird flies at 90 miles per hour and the speed of the train is 60 miles per hour. (b) the bird flies at 60 miles per hour and the speed of the train is 90 miles per hour

3. A tennis championship is played on a knock-out basis, i.e., a player is out of the tournament when he loses a match. (a) How many players participate in the tournament if 15 matches are totally played? (b) How many matches are played in the tournament if 50 players totally participate?

4. When I add 4 times my age 4 years from now to 5 times my age 5 years from now, I get 10 times my current age. How old will I be 3 years from now?

5. A rich merchant had collected many gold coins. He did not want anybody to know about them. One day, his wife asked, "How many gold coins do we have?" After pausing a moment, he replied, "Well! If I divide the coins into two unequal numbers, then 37 times the difference between the two numbers equals the difference between the squares of the two numbers." The wife looked puzzled. Can you help the merchant's wife by finding out how many gold R

6. A set of football matches is to be organized in a "round-robin" fashion, i.e., every participating team plays a match against every other team once and only once. If 21 matches are totally played, how many teams participated?

7. Glenn and Jason each have a collection of cricket balls. Glenn said that if Jason would give him 2 of his balls they would have an equal number; but, if Glenn would give Jason 2 of his balls, Jason would have 2 times as many balls as Glenn. How many balls does Jason have?

8. Suppose 8 monkeys take 8 minutes to eat 8 bananas. (a) How many minutes would it take 3 monkeys to eat 3 bananas? (b) How many monkeys would it take to eat 48 bananas in 48 minutes

9. It was vacation time, and so I decided to visit my cousin's home. What a grand time we had! In the mornings, we both would go for a jog. The evenings were spent on the tennis court. Tiring as these activities were, we could manage only one per day, i.e., either we went for a jog or played tennis each day. There were days when we felt lazy and stayed home all day long. Now, there were 12 mornings when we did nothing, 18 evenings when we stayed at home, and a total of 14 days when we jogged or played tennis. For how many days did I stay at my cousin's place?

10. A 31" x 31" square metal plate needs to be fixed by a carpenter on to a wooden board. The carpenter uses nails all along the edges of the square such that there are 32 nails on each side of the square. Each nail is at the same distance from the neighboring nails. How many nails does the carpenter use?


Answer and Explanation.

1. F + C + T = 100-------------eq1 15F + C + 0.25T = 100-------------eq2 eq1=eq2 .solve to get F=3T/56 ;F=3,T=56,C=41
2. a) There is no need to consider their meeting pt at all.the train has been running for 90miles/(60miles/hr)=1.5hrs.bird flies till train reaches destination frm strting pt.so bird flies for1.5hrs at the vel given(90).so dist=1.5*90=135miles b) time of train=1hr.so dist of bird=60*1=60miles
3. (a) u don't need to sum it up.since it's a knock out only 1 person emerges winner finally.so15+1=16is answer.becos after15 matches finally we shud've 15losers and 1winner.(b) 49:its always one less than no of players as per the idea given above.so no need to check okay cos its always true.ans is 49.
4. Let x= current age 4(x+4)+5(x+5)=10x ;so x=R 41 years
5. 37(x-y)=x^2-y^2. u no tht x^2-y^2=(x-y)(x+y).so (x-y) cancels on both sides to give x+y=37.so sum of unequal halves=37 which is the req answer.
6. R ans:7 teams okay.for a match u need 2 teams.suppose there r totally 'n 'teams.Now uve to choose 2 teams out of 'n' teams.so answer =no of such choices=no. of possible combinations. So we've ans = nC2(ncombination2)=21;solve to get n=7.Sol: n(n-1)/2=21. so n=7.if u don't understand c the graph beloweach team plays no. of matches=no of teams ahead of it. One bar '' represents one team. ------------7 6 5 4 3 2 1 0 -----------21last team is written as 0 matches becos this team has already played with all other teams-hence sum of matches =6+5+4+3+2+1=21 which is correct only if no of teams =7
7. R 141. G+2=j-22. 2(G-2)=J+2.solve these 2 to get J=14
8. a). Sol:each mky takes 8 min to eat a banana b).ans:8m=48 m=6
9. Use sets and venn diagram to solve such questions.a,b ,aub,anb etc.12=tennis+leave18=jog +leaveso jog-tennis=6again jog+tennis=14.so solve and get jog=10,leave=8,tennis=4.so tot=22
10. Ans= 32*2 + 30*2=124