87931 ÷ 7 = 12561 R4
We're going to perform division on 87931 with 7 as the divisor.

Step 1:
7 goes into 8 1 times with a remainder of 1.
Write down 1 as next digit of of the result. 
Result so far: 1
Subtract 7 from 8 to get 1.
Bring next digit (7) of the dividend behind the 1 and repeat the process: 17 / 7

Step 2:
7 goes into 17 2 times with a remainder of 3.
Write down 2 as next digit of of the result. 
Result so far: 12
Subtract 14 from 17 to get 3.
Bring next digit (9) of the dividend behind the 3 and repeat the process: 39 / 7

Step 3:
7 goes into 39 5 times with a remainder of 4.
Write down 5 as next digit of of the result. 
Result so far: 125
Subtract 35 from 39 to get 4.
Bring next digit (3) of the dividend behind the 4 and repeat the process: 43 / 7

Step 4:
7 goes into 43 6 times with a remainder of 1.
Write down 6 as next digit of of the result. 
Result so far: 1256
Subtract 42 from 43 to get 1.
Bring next digit (1) of the dividend behind the 1 and repeat the process: 11 / 7

Step 5:
7 goes into 11 1 times with a remainder of 4.
Write down 1 as next digit of of the result. 
Result so far: 12561
Subtract 7 from 11 to get 4.

The final result is 12561 with a remainder of 4.