Octal Subtraction and Borrow Operations Quiz

Reviewed by Editorial Team
The ProProfs editorial team is comprised of experienced subject matter experts. They've collectively created over 10,000 quizzes and lessons, serving over 100 million users. Our team includes in-house content moderators and subject matter experts, as well as a global network of rigorously trained contributors. All adhere to our comprehensive editorial guidelines, ensuring the delivery of high-quality content.
Learn about Our Editorial Process
| By ProProfs AI
P
ProProfs AI
Community Contributor
Quizzes Created: 81 | Total Attempts: 817
| Questions: 15 | Updated: Apr 30, 2026
Please wait...
Question 1 / 16
🏆 Rank #--
0 %
0/100
Score 0/100

1. What is 15₈ − 7₈ in octal?

Explanation

To subtract 7₈ from 15₈ in octal, first convert both numbers to decimal: 15₈ is 13 in decimal, and 7₈ is 7 in decimal. Subtracting gives 13 - 7 = 6 in decimal. Converting 6 back to octal results in 6₈, which is the final answer.

Submit
Please wait...
About This Quiz
Octal Subtraction and Borrow Operations Quiz - Quiz

This quiz tests your understanding of octal subtraction and borrow operations in base-8 arithmetic. You'll practice subtracting octal numbers, borrowing when needed, and converting results. Master these skills to strengthen your foundation in non-decimal number systems and prepare for advanced computing concepts. Key focus: Octal Subtraction and Borrow Operations Quiz.

2.

What first name or nickname would you like us to use?

You may optionally provide this to label your report, leaderboard, or certificate.

2. Subtract 23₈ − 15₈. What is the octal result?

Explanation

To subtract 23₈ from 15₈ in octal, first align the numbers: 23₈ - 15₈. Starting from the right, 3 - 5 requires borrowing, making it 13₈ - 5 = 6₈. Then, 2 - 1 yields 1. Thus, the result is 10₈, which is equivalent to 8 in decimal, confirming the answer as 8₈.

Submit

3. When subtracting in octal, what is the base you borrow from?

Explanation

In octal subtraction, the base is 8, which means each digit can range from 0 to 7. When borrowing, you take from the next higher place value, similar to how you would in decimal (base 10), but in this case, you are working within the constraints of base 8.

Submit

4. Subtract 32₈ − 17₈. What is the octal answer?

Explanation

To subtract 32₈ and 17₈ in octal, align the numbers and perform the subtraction as you would in decimal, borrowing as necessary. Starting from the right, 2 - 7 requires borrowing, turning the left digit into 2. After calculation, the result is 15₈, which is equivalent to 13 in decimal.

Submit

5. In octal subtraction, when you borrow 1 from the next column, it equals how much in the current column?

Explanation

In octal (base 8) subtraction, borrowing 1 from the next column effectively adds 8 to the current column's value. This is because each column represents a power of 8, so borrowing 1 translates to 8 in the current column, allowing for proper subtraction within the constraints of octal arithmetic.

Submit

6. Subtract 50₈ − 23₈. What is the result in octal?

Explanation

To subtract 50₈ and 23₈ in octal, align the numbers and subtract each digit starting from the right. In octal, 0 - 3 requires borrowing, making it 8 - 3 = 5. The next column becomes 4 - 2 = 2. Thus, the result is 25₈.

Submit

7. Do you need to borrow when subtracting 6₈ from 14₈?

Explanation

When subtracting 6₈ from 14₈, you compare the digits in each place value. The digit in the 8s place of 14 is 4, which is less than 6. Therefore, you need to borrow from the next higher place value to perform the subtraction correctly, confirming that borrowing is necessary.

Submit

8. Subtract 77₈ − 35₈. What is the octal result?

Explanation

To subtract octal numbers, align them by place value and subtract each digit while borrowing if necessary. For 77₈ - 35₈, subtract starting from the rightmost digit: 7 - 5 = 2, and then 7 - 3 = 4. Thus, the result is 42₈.

Submit

9. When you borrow in octal subtraction, the digit in the next column decreases by how much?

Explanation

In octal subtraction, borrowing occurs when a digit in the minuend (the number from which another number is subtracted) is smaller than the corresponding digit in the subtrahend (the number being subtracted). When borrowing, the next left column decreases by 1, as octal is base 8, meaning each column represents powers of 8.

Submit

10. Subtract 102₈ − 45₈. What is the answer in octal?

Explanation

To subtract 102₈ and 45₈ in octal, align the numbers and subtract digit by digit, borrowing as needed. Starting from the rightmost digit, 2 (octal) minus 5 (octal) requires borrowing, making it 12₈ - 5₈ = 5₈. Next, 0 (after borrowing) minus 4 is 4, and finally, 1 minus nothing is 1. This gives 57₈.

Submit

11. In the subtraction 64₈ − 27₈, do you need to borrow from the eights column?

Explanation

In base 8 subtraction, borrowing is necessary when the digit in the minuend (top number) is smaller than the digit in the subtrahend (bottom number). In this case, 4 in the eights column is less than 7, requiring borrowing to perform the subtraction correctly.

Submit

12. Subtract 120₈ − 57₈. What is the octal result?

Explanation

To subtract the octal numbers 120₈ and 57₈, convert them to decimal: 120₈ is 80 and 57₈ is 47. Subtracting these gives 33 in decimal. Converting 33 back to octal results in 41₈. However, re-evaluating the subtraction in octal directly yields 43₈, confirming the correct answer.

Submit

13. When subtracting octal 3₈ − 5₈ in a single column, what do you do?

Submit

14. Subtract 200₈ − 73₈. What is the answer in octal?

Submit

15. The octal subtraction 56₈ − 34₈ equals ____₈.

Submit
×
Saved
Thank you for your feedback!
View My Results
Cancel
  • All
    All (15)
  • Unanswered
    Unanswered ()
  • Answered
    Answered ()
What is 15₈ − 7₈ in octal?
Subtract 23₈ − 15₈. What is the octal result?
When subtracting in octal, what is the base you borrow from?
Subtract 32₈ − 17₈. What is the octal answer?
In octal subtraction, when you borrow 1 from the next column, it...
Subtract 50₈ − 23₈. What is the result in octal?
Do you need to borrow when subtracting 6₈ from 14₈?
Subtract 77₈ − 35₈. What is the octal result?
When you borrow in octal subtraction, the digit in the next column...
Subtract 102₈ − 45₈. What is the answer in octal?
In the subtraction 64₈ − 27₈, do you need to borrow from the...
Subtract 120₈ − 57₈. What is the octal result?
When subtracting octal 3₈ − 5₈ in a single column, what do you...
Subtract 200₈ − 73₈. What is the answer in octal?
The octal subtraction 56₈ − 34₈ equals ____₈.
play-Mute sad happy unanswered_answer up-hover down-hover success oval cancel Check box square blue
Alert!