4239 ÷ 5 = 847 R4
Let's divide 4239 by 5.

Step 1:
5 goes into 4 0 times with a remainder of 4.
Write down 0 as next digit of of the result. 
Result so far: 0
Subtract 0 from 4 to get 4.
Bring next digit (2) of the dividend behind the 4 and repeat the process: 42 / 5

Step 2:
5 goes into 42 8 times with a remainder of 2.
Write down 8 as next digit of of the result. 
Result so far: 8
Subtract 40 from 42 to get 2.
Bring next digit (3) of the dividend behind the 2 and repeat the process: 23 / 5

Step 3:
5 goes into 23 4 times with a remainder of 3.
Write down 4 as next digit of of the result. 
Result so far: 84
Subtract 20 from 23 to get 3.
Bring next digit (9) of the dividend behind the 3 and repeat the process: 39 / 5

Step 4:
5 goes into 39 7 times with a remainder of 4.
Write down 7 as next digit of of the result. 
Result so far: 847
Subtract 35 from 39 to get 4.

The final result is 847 with a remainder of 4.