40006 ÷ 3 = 13335 R1
We're going to perform division on 40006 with 3 as the divisor.

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

Step 2:
3 goes into 10 3 times with a remainder of 1.
Write down 3 as next digit of of the result. 
Result so far: 13
Subtract 9 from 10 to get 1.
Bring next digit (0) of the dividend behind the 1 and repeat the process: 10 / 3

Step 3:
3 goes into 10 3 times with a remainder of 1.
Write down 3 as next digit of of the result. 
Result so far: 133
Subtract 9 from 10 to get 1.
Bring next digit (0) of the dividend behind the 1 and repeat the process: 10 / 3

Step 4:
3 goes into 10 3 times with a remainder of 1.
Write down 3 as next digit of of the result. 
Result so far: 1333
Subtract 9 from 10 to get 1.
Bring next digit (6) of the dividend behind the 1 and repeat the process: 16 / 3

Step 5:
3 goes into 16 5 times with a remainder of 1.
Write down 5 as next digit of of the result. 
Result so far: 13335
Subtract 15 from 16 to get 1.

The final result is 13335 with a remainder of 1.