Subtract octal number (2546)₈ from (5142)₈

$\begin{matrix} & \overset{4}{\cancel{5}} & \overset{0}{\cancel{1}} & \overset{3}{\cancel{4}} & 2 \ - & 2 & 5 & 4 & 6 \ \hline & \bold{2} & \bold{3} & \bold{7} & \bold{4} \end{matrix}$

Therefore, (5142)₈ - (2546)₈ = (2374)₈

Explanation

1. 2 - 6, here 6 is greater than 2 so we borrow 1 from next significant digit 4 and it becomes 3. Now 2 becomes 2 + 8 = 10 and 10 - 6 = 4.
2. 3 - 4, again 4 is greater than 3 so we borrow 1 from next significant digit 1 and it becomes 0. Current digit 3 becomes 8 + 3 = 11. Lastly, 11 - 4 = 7.
3. 0 - 5, here 5 is greater than 0. Borrowing 1 from next significant digit 5 makes it 4. Current digit 0 becomes 0 + 8 = 8. Lastly, 8 - 5 = 3.
4. 4 - 2 = 2.