15143 ÷ 4 = 3785 R3
We're going to perform division on 15143 with 4 as the divisor.

Step 1:
4 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 (5) of the dividend behind the 1 and repeat the process: 15 / 4

Step 2:
4 goes into 15 3 times with a remainder of 3.
Write down 3 as next digit of of the result. 
Result so far: 3
Subtract 12 from 15 to get 3.
Bring next digit (1) of the dividend behind the 3 and repeat the process: 31 / 4

Step 3:
4 goes into 31 7 times with a remainder of 3.
Write down 7 as next digit of of the result. 
Result so far: 37
Subtract 28 from 31 to get 3.
Bring next digit (4) of the dividend behind the 3 and repeat the process: 34 / 4

Step 4:
4 goes into 34 8 times with a remainder of 2.
Write down 8 as next digit of of the result. 
Result so far: 378
Subtract 32 from 34 to get 2.
Bring next digit (3) of the dividend behind the 2 and repeat the process: 23 / 4

Step 5:
4 goes into 23 5 times with a remainder of 3.
Write down 5 as next digit of of the result. 
Result so far: 3785
Subtract 20 from 23 to get 3.

The final result is 3785 with a remainder of 3.