Let's divide 809171 by 21
Our goal is to divide 809171 by 21.

Step 1:
21 can be fit into 8 0 times, resulting in a remainder of 8.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtracting 0 from 8 leaves us with 8.
Take the next digit (0) from the dividend and append it to 8, then repeat: 80 / 21

Moving on to step 2:
21 goes into 80 3 times with a remainder of 17.
The number 3 becomes the next digit in our result. 
Result so far: 3.0
If we subtract 63 from 80, we get 17.
Append the next digit (9) from the dividend to 17 and continue with: 179 / 21

Let's proceed to step 3:
179 divided by 21 is 8 with a remainder of 11.
Use 8 as the next digit of our solution. 
Result so far: 38.0
If we subtract 168 from 179, we get 11.
Fetch the next digit (1) from the dividend, attach it to 11 and continue: 111 / 21

On to step 4:
The number 21 fits into 111 5 times, leaving a remainder of 6.
Put 5 as the next digit of the answer. 
Result so far: 385.0
If we subtract 105 from 111, we get 6.
Take the next digit (7) from the dividend and append it to 6, then repeat: 67 / 21

Let's proceed to step 5:
21 goes into 67 3 times with a remainder of 4.
Record the quotient 3 as the next digit in the result. 
Result so far: 3853.0
Deduct 63 from 67 and we're left with 4.
Take the next digit (1) from the dividend and append it to 4, then repeat: 41 / 21

On to step 6:
41 divided by 21 is 1 with a remainder of 20.
The next digit of our result is 1. 
Result so far: 38531.0
Subtract 21 from 41 to get 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:
200 divided by 21 is 9 with a remainder of 11.
Put 9 as the next digit of the answer. 
Result so far: 38531.9
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.

Going ahead to step 8:
110 divided by 21 is 5 with a remainder of 5.
Record the quotient 5 as the next digit in the result. 
Result so far: 38531.95
The remainder is 5 after subtracting 105 from 110.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Going ahead to step 9:
The number 21 fits into 50 2 times, leaving a remainder of 8.
Use 2 as the next digit of our solution. 
Result so far: 38531.952
If we take 42 away from 50, we end up with 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:
If we divide 80 by 21, we get 3 and a remainder of 17.
The number 3 becomes the next digit in our result. 
Result so far: 38531.9523
If we take 63 away from 80, we end up 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.

On to step 11:
21 can be fit into 170 8 times, resulting in a remainder of 2.
Put 8 as the next digit of the answer. 
Result so far: 38531.95238
If we subtract 168 from 170, we get 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Let's proceed to step 12:
The number 21 fits into 20 0 times, leaving a remainder of 20.
The number 0 becomes the next digit in our result. 
Result so far: 38531.95238
Deduct 0 from 20 and we're left 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.

On to step 13:
21 goes into 200 9 times with a remainder of 11.
Write down 9 as next digit of the result. 
Result so far: 38531.9523809
The remainder is 11 after subtracting 189 from 200.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

Step 14:
If we divide 110 by 21, we get 5 and a remainder of 5.
The next digit of our result is 5. 
Result so far: 38531.95238095
Deduct 105 from 110 and we're left 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 38531.95238095 with a remainder of 5e-09.