Computer Fundamentals Multiple choice Questions and Answers on Booth’s Algorithm for Freshers

1. Which of the following is used for binary multiplication?

a) Restoring Multiplication
b) Booth’s Algorithm
c) Pascal’s Rule
d) Digit-by-digit multiplication

Answer: b

Explanation: The Booth’s Algorithm is used for the multiplication of binary numbers. It is basically used for the multiplication of 2 signed numbers. This is a very important algorithm in binary arithmetic.

2. One extra bit is added on the left of a binary number, in case of Binary Multiplication using Booth’s Algorithm.

a) True
b) False

Answer: a

Explanation: The statement is true as an extra bit is added when we multiply 2 binary numbers by using Booth’s.
Let us take an example if we multiply 2 * – 3.
The first step is to obtain the binary equivalents.
Hence, 2=10 and -3=01.
Now after adding the extra bit 2=010 and -3=101.
We add 0 in case of positive numbers whereas 1 in negative numbers.

3. The binary number obtained after applying RSC on 11010 will be ___________

a) 11101
b) 10100
c) 01101
d) 01000

Answer: c

Explanation: RSC stands for Right-Shift Circulant. So, whenever the numbers are shifted to the right an extra 0 bit is added to the left. Here, after the right shift of 11010, the number obtained will be 01101.

4. The result of >> of 11001 by 3-bits will be ______________

a) 01000
b) 01111
c) 00011
d) 11111

Answer: a

Explanation: >> is the bitwise left shift operator in binary arithmetic.
Applying >>(left-shift) by 3-bits on the number 11001 will result in 3 zeroes on the right, i.e., 01000.

5. Booth’s Algorithm is applied on _____________

a) decimal numbers
b) binary numbers
c) hexadecimal numbers
d) octal Numbers

Answer: b

Explanation: Booth’s Algorithm is applied only on signed and unsigned binary numbers.
Although, the values of other number systems can be converted to binary, and then the multiplication could be performed.

6. If Booth’s Multiplication is performed on the numbers 22*3, then what is 3 referred to as __________

a) accumulator
b) multiplicand
c) quotient
d) multiplier

Answer: d

Explanation: It is referred to as the multiplier. Multiplier is denoted by Q in booth’s algorithm. 22 is called the multiplicand. These numbers are first converted to their binary equivalents and further the multiplication is performed.

7. What is the default value of accumulator in booth’s multiplication of two 4-bit binary numbers?

a) 0
b) 1
c) 0000
d) 00000

Answer: d

Explanation: The correct answer is d because in case of Booth’s algorithm an extra bit is always added to the binary numbers. The 4-bit binary numbers become 5-bit numbers after adding the extra bit. Accumulator is always assigned 0 bits of the order of the binary numbers whose multiplication is to be performed.

8. What is the value of n in multiplication of 110* 1000?

a) 2
b) 3
c) 4
d) 0

Answer: a

Explanation: In Booth’s, n denotes the number of bits that the higher binary number has when multiplication is performed. Here, since there are 4 bits in 1000, the answer is n=4.

9. What will be the value obtained after multiplication of (-2) * (-3) using Booth’s Algorithm?

a) 6
b) -6
c) -2
d) -3

Answer: a

Explanation: After applying the procedure of Booth’s Algorithm, the value obtained will be 6. Even though the result is obtained in its 2’s complement for but then it is reconverted to its normalized form. Also, the value obtained after decimal multiplication is the same as the value obtained after binary multiplication.

10. What does the data transfer instruction STA stand for?

a) Store Accumulator
b) Send Accumulator
c) Send Action
d) Store Action

Answer: a

Explanation: STA is a data transfer instruction given whenever a value is to be copied on the accumulator. It is used for the fetch operation.