**Digital Circuits Questions and Answers – Arithmetic Operation**

This set of Digital Electronics/Circuits Multiple Choice Questions & Answers (MCQs) focuses on “Arithmetic Operation”

**1. What is the addition of the binary numbers 11011011010 and 010100101?**

a) 0111001000

b) 1100110110

c) 11101111111

d) 10011010011

**Answer: c**

**Explanation:** The rules for Binary Addition are :

0 + 0 = 0

0 + 1 = 1

1 + 0 = 1

1 + 1 = 0 ( Carry 1)

1 1 1 0 1 1 0 1 1 0 1 0 + 0 0 0 1 0 1 0 0 1 0 1 _______________________ 1 1 1 0 1 1 1 1 1 1 1 _______________________

**2. Perform binary addition: 101101 + 011011 = ?**

a) 011010

b) 1010100

c) 101110

d) 1001000

**Answer: d**

**Explanation:**The rules for Binary Addition are :

0 + 0 = 0

0 + 1 = 1

1 + 0 = 1

1 + 1 = 0 ( Carry 1)

1 1 1 1 1 1 1 0 1 1 0 1 + 0 1 1 0 1 1 _______________ 1 0 0 1 0 0 0 _______________

Therefore, the addition of 101101 + 011011 = 1001000.

**3. Perform binary subtraction: 101111 – 010101 = ?**

a) 100100

b) 010101

c) 011010

d) 011001

**Answer: c**

**Explanation:** The rules for Binary Subtraction are :

0 – 0 = 0

0 – 1 = 1 ( Borrow 1)

1 – 0 = 1

1 – 1 = 0

1 0 1 1 1 1 - 0 1 0 1 0 1 ____________ 0 1 1 0 1 0 _____________

Therefore, The subtraction of 101111 – 010101 = 011010.

**4. Binary subtraction of 100101 – 011110 is**

a) 000111

b) 111000

c) 010101

d) 101010

**Answer: a**

**Explanation:** The rules for Binary Subtraction are :

0 – 0 = 0

0 – 1 = 1 ( Borrow 1)

1 – 0 = 1

1 – 1 = 0

1 0 0 1 0 1 - 0 1 1 1 1 0 ___________ 0 0 0 1 1 1 ___________

Therefore, The subtraction of 100101 – 011110 = 000111.

**5. Perform multiplication of the binary numbers: 01001 × 01011 = ?**

a) 001100011

b) 110011100

c) 010100110

d) 101010111

**Answer: a**

**Explanation:** The rules for binary multiplication are:

0 * 0 = 0

0 * 1 = 0

1 * 0 = 0

1 * 1 = 1

0 1 0 0 1 x 0 1 0 1 1 ____________ 0 1 0 0 1 0 1 0 0 1 0 0 0 0 0 0 0 0 0 1 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 ___________________ 0 0 1 1 0 0 0 1 1 ___________________

Therefore, 01001 × 01011 = 001100011.

**6. 100101 × 0110 = ?**

a) 1011001111

b) 0100110011

c) 101111110

d) 0110100101

**Answer**:

**c**

**Explanation:**The rules for binary multiplication are:

0 * 0 = 0

0 * 1 = 0

1 * 0 = 0

1 * 1 = 1

1 0 0 1 0 1 x 0 1 1 0 ___________ 0 0 0 0 0 0 1 0 0 1 0 1 0 1 0 0 1 0 1 0 0 0 0 0 0 0 0 0 0 0 __________________ 0 1 1 0 1 1 1 1 0 ___________________

Therefore, 100101 x 0110 = 011011110.

**7. On multiplication of (10.10) and (01.01), we get**

a) 101.0010

b) 0010.101

c) 011.0010

d) 110.0011

**Answer: c**

**Explanation:**The rules for binary multiplication are:

0 * 0 = 0

0 * 1 = 0

1 * 0 = 0

1 * 1 = 1

1 0.1 0 x 0 1.0 1 __________ 1 0 1 0 0 0 0 0 0 1 0 1 0 0 0 0 0 0 0 0 0 0 _______________ 0 1 1.0 0 1 0 _________________

Therefore, 10.10 x 01.01 = 011.0010.

**8. Divide the binary numbers: 111101 ÷ 1001 and find the remainder**

a) 0010

b) 1010

c) 1100

d) 0011

**Answer: d**

**Explanation:**Binary Division is accomplished using long division method.

1 0 0 1 ) 1 1 1 1 0 1 ( 1 1 1 0 0 1 __________ 0 1 1 0 0 1 0 0 1 ___________ 0 1 1 1

Therefore, the remainder of 111101 ÷ 1001 = 0111.

**9. Divide the binary number (011010000) by (0101) and find the quotient**

a) 100011

b) 101001

c) 110010

d) 010001

**Answer: b**

**Explanation:**

0 1 0 1 ) 0 1 1 0 1 0 0 0 0 ( 0 1 0 1 1 1 0 0 0 0 _____________________ 0 1 1 0 1 0 0 1 0 1 ______________ 0 1 0 0 0 0 0 0 0 0 0 0 ______________________ 1 0 0 0 0 0 0 1 0 1 ____________________ 0 1 0 1 1 0 0 0 0 1 0 1 ____________________ 1 0 0 0 1 0 0 0 0 1 0 1 ________________________ 1 1 1 0 1 0 0 0 0 1 0 1 ________________________ 1 0 1 0 1 0 0 1 0 1 ________________________ 1 0 0 0 0

Therefore, the quotient of 011010000 ÷ 1001 = 101001.

**10. Binary subtraction of 101101 – 001011 = ?**

a) 100010

b) 010110

c) 110101

d) 101100

**Answer: a**

**Explanation:** The rules for binary subtraction are:

0 – 0 = 0

0 – 1 = 1 ( Borrow 1)

1 – 0 = 1

1 – 1 = 0

1 0 1 1 0 1 - 0 0 1 0 1 1 ____________ 1 0 0 0 1 0 ____________

Therefore, the subtraction of 101101 – 001011 = 100010.

**« Prev – Digital Circuits Questions and Answers – Number System – 2**

**» Next – Digital Circuits Questions and Answers – 1’s, 2’s, 9’s & 10’s Complements – 1**