20935 ÷ 3 = 6978 R1
Let's divide 20935 by 3.

Step 1:
3 goes into 2 0 times with a remainder of 2.
Write down 0 as next digit of of the result. 
Result so far: 0
Subtract 0 from 2 to get 2.
Bring next digit (0) of the dividend behind the 2 and repeat the process: 20 / 3

Step 2:
3 goes into 20 6 times with a remainder of 2.
Write down 6 as next digit of of the result. 
Result so far: 6
Subtract 18 from 20 to get 2.
Bring next digit (9) of the dividend behind the 2 and repeat the process: 29 / 3

Step 3:
3 goes into 29 9 times with a remainder of 2.
Write down 9 as next digit of of the result. 
Result so far: 69
Subtract 27 from 29 to get 2.
Bring next digit (3) of the dividend behind the 2 and repeat the process: 23 / 3

Step 4:
3 goes into 23 7 times with a remainder of 2.
Write down 7 as next digit of of the result. 
Result so far: 697
Subtract 21 from 23 to get 2.
Bring next digit (5) of the dividend behind the 2 and repeat the process: 25 / 3

Step 5:
3 goes into 25 8 times with a remainder of 1.
Write down 8 as next digit of of the result. 
Result so far: 6978
Subtract 24 from 25 to get 1.

The final result is 6978 with a remainder of 1.