Computer Fundamentals Multiple choice Questions and Answers on IEEE 32 and 64 bit for Freshers

1. Binary addition of 1 + 1 gives the result _____________

a) 0
b) 1
c) 2
d) 10

Answer: a

Explanation: The result obtained is 0 with a carry of 1. This carry obtained is added to the next higher column. Binary system can have only two numbers 0 and 1.

2. 4-bit is a valid IEEE- format.

a) True
b) False

Answer: b

Explanation: The two main IEEE formats are 16-bit and 32-bit. No format of 4-bit exists. Further, 8-bit format also exists.
In IEEE format, there are certain bits allotted to sign, exponent and mantissa.

3. The result of 0 – 1 in binary is ______________

a) 0
b) 1
c) 11
d) 10

Answer: b

Explanation: The binary subtraction 0 – 1 gives the result 1. A borrow of 1 is although generated and is removed from the next higher column.

4. The complement of any number can be given by a general term _______________

a) Bn – 1 – N
b) Bn -1 + N
c) Bn +1 – N
d) Bn +1 + N

Answer: a

Explanation: Complement of a number can be given by the term :
C= Bn – 1 – N.
Here,
B= base
n= number of digits
N= the number.

5. The IEEE standard followed by almost all the computers for floating point arithmetic _____

a) IEEE 260
b) IEEE 488
c) IEEE 754
d) IEEE 610

Answer: c

Explanation: Most computers follow the IEEE 754 bit format for floating point arithmetic. IEEE stands for electrical and electronic engineers. It has all the floating point arithmetic specifications.

6. Which of the following is often called the double precision format?

a) 64-bit
b) 8-bit
c) 32-bit
d) 128-bit

Answer: a

Explanation: The 64-bit format is referred to as the double precision format. It has 1 sign bit, 8 exponent bits and 23 bits for the mantissa.

7. What is NaN in IEEE standards?

a) Not arithmetic
b) Not a negation
c) Not a number
d) Not a Node

Answer: c

Explanation: It stands for not a number in IEEE standards. A NaN is obtained whenever a result id indeterminate like whenever anything is divided by 0.

8. The result that is smaller than the smallest number obtained is referred to as ___________

a) NaN
b) Underflow
c) Smallest
d) Mantissa

Answer: b

Explanation: It is referred to as underflow. Nan stands for not a number. The mantissa is the part after the decimal.

9. The number of sign bits in a 32-bit IEEE format _________

a) 1
b) 11
c) 9
d) 23

Answer: a

Explanation: There is only 1 sign bit in all the standards. In a 32-bit format, there is 1 sign bit, 8 bits for the exponent and 23 bits for the mantissa.

10. Express the decimal format of the signed binary number (101010)2 .

a) 10
b) 12
c) -12
d) -10

Answer: d

Explanation: The first bit is the sign bit whereas the rest of the bits are magnitude bits. So the number is: 01010 =23 * 1 + 21 * 1 =8+2 =10.
But, the sign bit is 1 ,
Therefore the answer is : (-2)10.