We look at the division of 829670 by 21 
Let's see how many times 21 fits into 829670.

Advancing to step 1:
If we divide 8 by 21, we get 0 and a remainder of 8.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Deduct 0 from 8 and we're left with 8.
Grab the next digit (2) from the dividend, add it to 8, then carry on: 82 / 21

Moving on to step 2:
When dividing 82 by 21, we get 3 with a remainder of 19.
Use 3 as the next digit of our solution. 
Result so far: 3.0
Subtracting 63 from 82 leaves us with 19.
Fetch the next digit (9) from the dividend, attach it to 19 and continue: 199 / 21

On to step 3:
When dividing 199 by 21, we get 9 with a remainder of 10.
Record the quotient 9 as the next digit in the result. 
Result so far: 39.0
Subtract 189 from 199 to get 10.
Take the next digit (6) from the dividend and append it to 10, then repeat: 106 / 21

Step 4:
When dividing 106 by 21, we get 5 with a remainder of 1.
Put 5 as the next digit of the answer. 
Result so far: 395.0
The remainder is 1 after subtracting 105 from 106.
Bring next digit (7) of the dividend behind the 1 and repeat the process: 17 / 21

On to step 5:
If we divide 17 by 21, we get 0 and a remainder of 17.
The number 0 becomes the next digit in our result. 
Result so far: 3950.0
Subtract 0 from 17 to get 17.
Take the next digit (0) from the dividend and append it to 17, then repeat: 170 / 21

Let's proceed to step 6:
The number 21 fits into 170 8 times, leaving a remainder of 2.
Put 8 as the next digit of the answer. 
Result so far: 39508.0
Subtract 168 from 170 to 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 7:
21 can be fit into 20 0 times, resulting in a remainder of 20.
The next digit of our result is 0. 
Result so far: 39508.0
If we subtract 0 from 20, we 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.

Let's proceed to step 8:
If we divide 200 by 21, we get 9 and a remainder of 11.
Use 9 as the next digit of our solution. 
Result so far: 39508.09
If we take 189 away from 200, we end up 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.

Advancing to step 9:
21 goes into 110 5 times with a remainder of 5.
Put 5 as the next digit of the answer. 
Result so far: 39508.095
Subtracting 105 from 110 leaves us 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.

Let's proceed to step 10:
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: 39508.0952
The remainder is 8 after subtracting 42 from 50.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Advancing to step 11:
21 can be fit into 80 3 times, resulting in a remainder of 17.
Record the quotient 3 as the next digit in the result. 
Result so far: 39508.09523
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.

Step 12:
21 can be fit into 170 8 times, resulting in a remainder of 2.
The next digit of our result is 8. 
Result so far: 39508.095238
If we take 168 away from 170, we end up 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 13:
21 goes into 20 0 times with a remainder of 20.
Write down 0 as next digit of the result. 
Result so far: 39508.095238
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.

Let's proceed to step 14:
21 goes into 200 9 times with a remainder of 11.
Record the quotient 9 as the next digit in the result. 
Result so far: 39508.09523809
Deduct 189 from 200 and we're left 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.

The final result is 39508.09523809 with a remainder of 1.1e-08.