39430 ÷ 3 = 13143 R1
We're going to perform division on 39430 with 3 as the divisor.

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

Step 2:
3 goes into 9 3 times with a remainder of 0.
Write down 3 as next digit of of the result. 
Result so far: 13
Subtract 9 from 9 to get 0.
Bring next digit (4) of the dividend behind the 0 and repeat the process: 4 / 3

Step 3:
3 goes into 4 1 times with a remainder of 1.
Write down 1 as next digit of of the result. 
Result so far: 131
Subtract 3 from 4 to get 1.
Bring next digit (3) of the dividend behind the 1 and repeat the process: 13 / 3

Step 4:
3 goes into 13 4 times with a remainder of 1.
Write down 4 as next digit of of the result. 
Result so far: 1314
Subtract 12 from 13 to get 1.
Bring next digit (0) of the dividend behind the 1 and repeat the process: 10 / 3

Step 5:
3 goes into 10 3 times with a remainder of 1.
Write down 3 as next digit of of the result. 
Result so far: 13143
Subtract 9 from 10 to get 1.

The final result is 13143 with a remainder of 1.