15403 ÷ 9 = 1711 R4
We're going to perform division on 15403 with 9 as the divisor.

Step 1:
9 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 / 9

Step 2:
9 goes into 15 1 times with a remainder of 6.
Write down 1 as next digit of of the result. 
Result so far: 1
Subtract 9 from 15 to get 6.
Bring next digit (4) of the dividend behind the 6 and repeat the process: 64 / 9

Step 3:
9 goes into 64 7 times with a remainder of 1.
Write down 7 as next digit of of the result. 
Result so far: 17
Subtract 63 from 64 to get 1.
Bring next digit (0) of the dividend behind the 1 and repeat the process: 10 / 9

Step 4:
9 goes into 10 1 times with a remainder of 1.
Write down 1 as next digit of of the result. 
Result so far: 171
Subtract 9 from 10 to get 1.
Bring next digit (3) of the dividend behind the 1 and repeat the process: 13 / 9

Step 5:
9 goes into 13 1 times with a remainder of 4.
Write down 1 as next digit of of the result. 
Result so far: 1711
Subtract 9 from 13 to get 4.

The final result is 1711 with a remainder of 4.