72003 ÷ 1 = 72003 R0
We're going to perform division on 72003 with 1 as the divisor.

Step 1:
1 goes into 7 7 times with a remainder of 0.
Write down 7 as next digit of of the result. 
Result so far: 7
Subtract 7 from 7 to get 0.
Bring next digit (2) of the dividend behind the 0 and repeat the process: 2 / 1

Step 2:
1 goes into 2 2 times with a remainder of 0.
Write down 2 as next digit of of the result. 
Result so far: 72
Subtract 2 from 2 to get 0.
Bring next digit (0) of the dividend behind the 0 and repeat the process: 0 / 1

Step 3:
1 goes into 0 0 times with a remainder of 0.
Write down 0 as next digit of of the result. 
Result so far: 720
Subtract 0 from 0 to get 0.
Bring next digit (0) of the dividend behind the 0 and repeat the process: 0 / 1

Step 4:
1 goes into 0 0 times with a remainder of 0.
Write down 0 as next digit of of the result. 
Result so far: 7200
Subtract 0 from 0 to get 0.
Bring next digit (3) of the dividend behind the 0 and repeat the process: 3 / 1

Step 5:
1 goes into 3 3 times with a remainder of 0.
Write down 3 as next digit of of the result. 
Result so far: 72003
Subtract 3 from 3 to get 0.

The final result is 72003 with a remainder of 0.