31512 ÷ 4 = 7878 R0
We're going to perform division on 31512 with 4 as the divisor.

Step 1:
4 goes into 3 0 times with a remainder of 3.
Write down 0 as next digit of of the result. 
Result so far: 0
Subtract 0 from 3 to get 3.
Bring next digit (1) of the dividend behind the 3 and repeat the process: 31 / 4

Step 2:
4 goes into 31 7 times with a remainder of 3.
Write down 7 as next digit of of the result. 
Result so far: 7
Subtract 28 from 31 to get 3.
Bring next digit (5) of the dividend behind the 3 and repeat the process: 35 / 4

Step 3:
4 goes into 35 8 times with a remainder of 3.
Write down 8 as next digit of of the result. 
Result so far: 78
Subtract 32 from 35 to get 3.
Bring next digit (1) of the dividend behind the 3 and repeat the process: 31 / 4

Step 4:
4 goes into 31 7 times with a remainder of 3.
Write down 7 as next digit of of the result. 
Result so far: 787
Subtract 28 from 31 to get 3.
Bring next digit (2) of the dividend behind the 3 and repeat the process: 32 / 4

Step 5:
4 goes into 32 8 times with a remainder of 0.
Write down 8 as next digit of of the result. 
Result so far: 7878
Subtract 32 from 32 to get 0.

The final result is 7878 with a remainder of 0.