We look at the division of 303869 by 21 
We want to divide 303869 by 21.

Advancing to step 1:
The number 21 fits into 3 0 times, leaving a remainder of 3.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtract 0 from 3 to get 3.
Take the next digit (0) from the dividend and append it to 3, then repeat: 30 / 21

On to step 2:
30 divided by 21 is 1 with a remainder of 9.
Use 1 as the next digit of our solution. 
Result so far: 1.0
The remainder is 9 after subtracting 21 from 30.
Fetch the next digit (3) from the dividend, attach it to 9 and continue: 93 / 21

Moving on to step 3:
The number 21 fits into 93 4 times, leaving a remainder of 9.
Put 4 as the next digit of the answer. 
Result so far: 14.0
If we subtract 84 from 93, we get 9.
Include the next digit (8) from the dividend after 9, then repeat: 98 / 21

Going ahead to step 4:
The number 21 fits into 98 4 times, leaving a remainder of 14.
The number 4 becomes the next digit in our result. 
Result so far: 144.0
The remainder is 14 after subtracting 84 from 98.
Append the next digit (6) from the dividend to 14 and continue with: 146 / 21

Moving on to step 5:
146 divided by 21 is 6 with a remainder of 20.
Use 6 as the next digit of our solution. 
Result so far: 1446.0
Subtract 126 from 146 to get 20.
Include the next digit (9) from the dividend after 20, then repeat: 209 / 21

Step 6:
If we divide 209 by 21, we get 9 and a remainder of 20.
Record the quotient 9 as the next digit in the result. 
Result so far: 14469.0
If we take 189 away from 209, we end up with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Advancing to step 7:
21 can be fit into 200 9 times, resulting in a remainder of 11.
Use 9 as the next digit of our solution. 
Result so far: 14469.9
Subtract 189 from 200 to get 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

Let's proceed to step 8:
When dividing 110 by 21, we get 5 with a remainder of 5.
Put 5 as the next digit of the answer. 
Result so far: 14469.95
If we subtract 105 from 110, we get 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Let's proceed to step 9:
21 goes into 50 2 times with a remainder of 8.
The next digit of our result is 2. 
Result so far: 14469.952
Subtract 42 from 50 to get 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Moving on to step 10:
When dividing 80 by 21, we get 3 with a remainder of 17.
Write down 3 as next digit of the result. 
Result so far: 14469.9523
Subtracting 63 from 80 leaves us with 17.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

Let's proceed to step 11:
21 goes into 170 8 times with a remainder of 2.
Put 8 as the next digit of the answer. 
Result so far: 14469.95238
Deduct 168 from 170 and we're left with 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Step 12:
20 divided by 21 is 0 with a remainder of 20.
Record the quotient 0 as the next digit in the result. 
Result so far: 14469.95238
Subtracting 0 from 20 leaves us with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Going ahead to step 13:
21 can be fit into 200 9 times, resulting in a remainder of 11.
Use 9 as the next digit of our solution. 
Result so far: 14469.9523809
Subtracting 189 from 200 leaves us with 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

On to step 14:
The number 21 fits into 110 5 times, leaving a remainder of 5.
Record the quotient 5 as the next digit in the result. 
Result so far: 14469.95238095
If we take 105 away from 110, we end up with 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

The final result is 14469.95238095 with a remainder of 5e-09.