1504 ÷ 3 = 501 R1
Let's divide 1504 by 3.

Step 1:
3 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 / 3

Step 2:
3 goes into 15 5 times with a remainder of 0.
Write down 5 as next digit of of the result. 
Result so far: 5
Subtract 15 from 15 to get 0.
Bring next digit (0) of the dividend behind the 0 and repeat the process: 0 / 3

Step 3:
3 goes into 0 0 times with a remainder of 0.
Write down 0 as next digit of of the result. 
Result so far: 50
Subtract 0 from 0 to get 0.
Bring next digit (4) of the dividend behind the 0 and repeat the process: 4 / 3

Step 4:
3 goes into 4 1 times with a remainder of 1.
Write down 1 as next digit of of the result. 
Result so far: 501
Subtract 3 from 4 to get 1.

The final result is 501 with a remainder of 1.