12931 ÷ 8 = 1616 R3
Let's divide 12931 by 8.

Step 1:
8 goes into 1 0 times with a remainder of 1.
Write down 0 as next digit of of the result. 
Result so far: 0
Subtract 0 from 1 to get 1.
Bring next digit (2) of the dividend behind the 1 and repeat the process: 12 / 8

Step 2:
8 goes into 12 1 times with a remainder of 4.
Write down 1 as next digit of of the result. 
Result so far: 1
Subtract 8 from 12 to get 4.
Bring next digit (9) of the dividend behind the 4 and repeat the process: 49 / 8

Step 3:
8 goes into 49 6 times with a remainder of 1.
Write down 6 as next digit of of the result. 
Result so far: 16
Subtract 48 from 49 to get 1.
Bring next digit (3) of the dividend behind the 1 and repeat the process: 13 / 8

Step 4:
8 goes into 13 1 times with a remainder of 5.
Write down 1 as next digit of of the result. 
Result so far: 161
Subtract 8 from 13 to get 5.
Bring next digit (1) of the dividend behind the 5 and repeat the process: 51 / 8

Step 5:
8 goes into 51 6 times with a remainder of 3.
Write down 6 as next digit of of the result. 
Result so far: 1616
Subtract 48 from 51 to get 3.

The final result is 1616 with a remainder of 3.