313956 ÷ 21 
Our goal is to divide 313956 by 21.

On to step 1:
3 divided by 21 is 0 with a remainder of 3.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we take 0 away from 3, we end up with 3.
Fetch the next digit (1) from the dividend, attach it to 3 and continue: 31 / 21

Let's proceed to step 2:
21 can be fit into 31 1 times, resulting in a remainder of 10.
Use 1 as the next digit of our solution. 
Result so far: 1.0
Subtract 21 from 31 to get 10.
Include the next digit (3) from the dividend after 10, then repeat: 103 / 21

Advancing to step 3:
If we divide 103 by 21, we get 4 and a remainder of 19.
Write down 4 as next digit of the result. 
Result so far: 14.0
Subtracting 84 from 103 leaves us with 19.
Fetch the next digit (9) from the dividend, attach it to 19 and continue: 199 / 21

Going ahead to step 4:
If we divide 199 by 21, we get 9 and a remainder of 10.
The number 9 becomes the next digit in our result. 
Result so far: 149.0
If we subtract 189 from 199, we get 10.
Bring next digit (5) of the dividend behind the 10 and repeat the process: 105 / 21

Going ahead to step 5:
105 divided by 21 is 5 with a remainder of 0.
Record the quotient 5 as the next digit in the result. 
Result so far: 1495.0
If we take 105 away from 105, we end up with 0.
Fetch the next digit (6) from the dividend, attach it to 0 and continue: 6 / 21

On to step 6:
6 divided by 21 is 0 with a remainder of 6.
Use 0 as the next digit of our solution. 
Result so far: 14950.0
The remainder is 6 after subtracting 0 from 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

On to step 7:
60 divided by 21 is 2 with a remainder of 18.
Record the quotient 2 as the next digit in the result. 
Result so far: 14950.2
Deduct 42 from 60 and we're left with 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

Moving on to step 8:
When dividing 180 by 21, we get 8 with a remainder of 12.
Put 8 as the next digit of the answer. 
Result so far: 14950.28
Subtract 168 from 180 to get 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Step 9:
The number 21 fits into 120 5 times, leaving a remainder of 15.
Write down 5 as next digit of the result. 
Result so far: 14950.285
Deduct 105 from 120 and we're left with 15.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

Going ahead to step 10:
The number 21 fits into 150 7 times, leaving a remainder of 3.
The number 7 becomes the next digit in our result. 
Result so far: 14950.2857
If we take 147 away from 150, we end up with 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

Advancing to step 11:
When dividing 30 by 21, we get 1 with a remainder of 9.
The next digit of our result is 1. 
Result so far: 14950.28571
If we take 21 away from 30, we end up with 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

On to step 12:
21 can be fit into 90 4 times, resulting in a remainder of 6.
The next digit of our result is 4. 
Result so far: 14950.285714
Subtracting 84 from 90 leaves us with 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

On to step 13:
When dividing 60 by 21, we get 2 with a remainder of 18.
The number 2 becomes the next digit in our result. 
Result so far: 14950.2857142
The remainder is 18 after subtracting 42 from 60.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

Going ahead to step 14:
The number 21 fits into 180 8 times, leaving a remainder of 12.
The next digit of our result is 8. 
Result so far: 14950.28571428
If we subtract 168 from 180, we get 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

After the division, we end up with 14950.28571428 and a remainder of 1.2e-08.