We look at the division of 172322 by 21 
We're looking to find how many times 21 goes into 172322.

Going ahead to step 1:
1 divided by 21 is 0 with a remainder of 1.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtracting 0 from 1 leaves us with 1.
Include the next digit (7) from the dividend after 1, then repeat: 17 / 21

Going ahead to step 2:
21 goes into 17 0 times with a remainder of 17.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 17 to get 17.
Fetch the next digit (2) from the dividend, attach it to 17 and continue: 172 / 21

Advancing to step 3:
If we divide 172 by 21, we get 8 and a remainder of 4.
Put 8 as the next digit of the answer. 
Result so far: 8.0
Subtracting 168 from 172 leaves us with 4.
Append the next digit (3) from the dividend to 4 and continue with: 43 / 21

Step 4:
If we divide 43 by 21, we get 2 and a remainder of 1.
The next digit of our result is 2. 
Result so far: 82.0
If we subtract 42 from 43, we get 1.
Append the next digit (2) from the dividend to 1 and continue with: 12 / 21

Moving on to step 5:
12 divided by 21 is 0 with a remainder of 12.
The next digit of our result is 0. 
Result so far: 820.0
Subtracting 0 from 12 leaves us with 12.
Take the next digit (2) from the dividend and append it to 12, then repeat: 122 / 21

Going ahead to step 6:
21 goes into 122 5 times with a remainder of 17.
Write down 5 as next digit of the result. 
Result so far: 8205.0
Subtracting 105 from 122 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.

Advancing to step 7:
The number 21 fits into 170 8 times, leaving a remainder of 2.
The next digit of our result is 8. 
Result so far: 8205.8
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.

Moving on to step 8:
21 goes into 20 0 times with a remainder of 20.
The number 0 becomes the next digit in our result. 
Result so far: 8205.8
The remainder is 20 after subtracting 0 from 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 9:
21 can be fit into 200 9 times, resulting in a remainder of 11.
The number 9 becomes the next digit in our result. 
Result so far: 8205.809
If we subtract 189 from 200, we 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.

Advancing to step 10:
21 can be fit into 110 5 times, resulting in a remainder of 5.
Put 5 as the next digit of the answer. 
Result so far: 8205.8095
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 11:
If we divide 50 by 21, we get 2 and a remainder of 8.
The next digit of our result is 2. 
Result so far: 8205.80952
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.

On to step 12:
When dividing 80 by 21, we get 3 with a remainder of 17.
Record the quotient 3 as the next digit in the result. 
Result so far: 8205.809523
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.

Moving on to step 13:
The number 21 fits into 170 8 times, leaving a remainder of 2.
The number 8 becomes the next digit in our result. 
Result so far: 8205.8095238
Subtracting 168 from 170 leaves us 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.

On to step 14:
When dividing 20 by 21, we get 0 with a remainder of 20.
Record the quotient 0 as the next digit in the result. 
Result so far: 8205.8095238
If we take 0 away from 20, 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.

The final result is 8205.8095238 with a remainder of 2e-08.