Let's solve each question from the
Decimal and Octal - MCQ worksheet step by step. The questions involve converting between
decimal (base-10) and
octal (base-8) number systems.
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Question 1: The octal equivalent of 32₁₀ is
We need to convert decimal
32 to octal.
Step-by-step conversion:
Divide 32 by 8:
- 32 ÷ 8 = 4 remainder
0
- 4 ÷ 8 = 0 remainder
4
Now read the remainders from bottom to top:
40₈
✔ Answer: b) 40₈
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Question 2: Which of the following is the octal equivalent of 428₁₀?
Convert
428 to octal.
Divide by 8 repeatedly:
- 428 ÷ 8 = 53 remainder
4
- 53 ÷ 8 = 6 remainder
5
- 6 ÷ 8 = 0 remainder
6
Read remainders from bottom to top:
654₈
✔ Answer: b) 654₈
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Question 3: The decimal equivalent of 65₈ is
Convert
65₈ (octal) to decimal.
Use place values (powers of 8):
- 6 × 8¹ = 6 × 8 = 48
- 5 × 8⁰ = 5 × 1 = 5
Add: 48 + 5 =
53₁₀
✔ Answer: c) 53₁₀
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Question 4: Which of the following is the decimal equivalent of 1574₈?
Convert
1574₈ to decimal.
Break it down:
- 1 × 8³ = 1 × 512 = 512
- 5 × 8² = 5 × 64 = 320
- 7 × 8¹ = 7 × 8 = 56
- 4 × 8⁰ = 4 × 1 = 4
Add: 512 + 320 = 832; 832 + 56 = 888; 888 + 4 =
892₁₀
✔ Answer: a) 892₁₀
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Question 5: The octal equivalent of 753₁₀ is
Convert
753 to octal.
Divide by 8:
- 753 ÷ 8 = 94 remainder
1
- 94 ÷ 8 = 11 remainder
6
- 11 ÷ 8 = 1 remainder
3
- 1 ÷ 8 = 0 remainder
1
Remainders from bottom to top:
1361₈
✔ Answer: d) 1361₈
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Question 6: Which of the following is the decimal equivalent of 5627₈?
Convert
5627₈ to decimal.
Break down:
- 5 × 8³ = 5 × 512 = 2560
- 6 × 8² = 6 × 64 = 384
- 2 × 8¹ = 2 × 8 = 16
- 7 × 8⁰ = 7 × 1 = 7
Add: 2560 + 384 = 2944; 2944 + 16 = 2960; 2960 + 7 =
2967₁₀
✔ Answer: a) 2967₁₀
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Question 7: The octal equivalent of 2081₁₀ is
Convert
2081 to octal.
Divide by 8:
- 2081 ÷ 8 = 260 remainder
1
- 260 ÷ 8 = 32 remainder
4
- 32 ÷ 8 = 4 remainder
0
- 4 ÷ 8 = 0 remainder
4
Remainders from bottom to top:
4041₈
✔ Answer: d) 4041₈
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✔ Final Answers Summary:
| Question | Answer |
|--------|--------|
| 1 | b) 40₈ |
| 2 | b) 654₈ |
| 3 | c) 53₁₀ |
| 4 | a) 892₁₀ |
| 5 | d) 1361₈ |
| 6 | a) 2967₁₀ |
| 7 | d) 4041₈ |
Let me know if you'd like a printable version or explanation in another format!
Parent Tip: Review the logic above to help your child master the concept of decimal to octal converter.