We divide 991959 by 21
Let's see how many times 21 fits into 991959.

Going ahead to step 1:
If we divide 9 by 21, we get 0 and a remainder of 9.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 9 to get 9.
Fetch the next digit (9) from the dividend, attach it to 9 and continue: 99 / 21

Let's proceed to step 2:
99 divided by 21 is 4 with a remainder of 15.
Write down 4 as next digit of the result. 
Result so far: 4.0
The remainder is 15 after subtracting 84 from 99.
Grab the next digit (1) from the dividend, add it to 15, then carry on: 151 / 21

On to step 3:
The number 21 fits into 151 7 times, leaving a remainder of 4.
The number 7 becomes the next digit in our result. 
Result so far: 47.0
The remainder is 4 after subtracting 147 from 151.
Fetch the next digit (9) from the dividend, attach it to 4 and continue: 49 / 21

On to step 4:
21 can be fit into 49 2 times, resulting in a remainder of 7.
Record the quotient 2 as the next digit in the result. 
Result so far: 472.0
Deduct 42 from 49 and we're left with 7.
Take the next digit (5) from the dividend and append it to 7, then repeat: 75 / 21

Moving on to step 5:
21 goes into 75 3 times with a remainder of 12.
The next digit of our result is 3. 
Result so far: 4723.0
Subtract 63 from 75 to get 12.
Append the next digit (9) from the dividend to 12 and continue with: 129 / 21

Going ahead to step 6:
If we divide 129 by 21, we get 6 and a remainder of 3.
Use 6 as the next digit of our solution. 
Result so far: 47236.0
If we subtract 126 from 129, we get 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

Step 7:
21 can be fit into 30 1 times, resulting in a remainder of 9.
Record the quotient 1 as the next digit in the result. 
Result so far: 47236.1
If we subtract 21 from 30, we get 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

Advancing to step 8:
The number 21 fits into 90 4 times, leaving a remainder of 6.
Put 4 as the next digit of the answer. 
Result so far: 47236.14
If we subtract 84 from 90, we get 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

Advancing to step 9:
21 can be fit into 60 2 times, resulting in a remainder of 18.
Record the quotient 2 as the next digit in the result. 
Result so far: 47236.142
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.

Advancing to step 10:
If we divide 180 by 21, we get 8 and a remainder of 12.
Use 8 as the next digit of our solution. 
Result so far: 47236.1428
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.

Let's proceed to step 11:
21 goes into 120 5 times with a remainder of 15.
Write down 5 as next digit of the result. 
Result so far: 47236.14285
The remainder is 15 after subtracting 105 from 120.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

Let's proceed to step 12:
150 divided by 21 is 7 with a remainder of 3.
The next digit of our result is 7. 
Result so far: 47236.142857
Deduct 147 from 150 and we're left 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.

On to step 13:
The number 21 fits into 30 1 times, leaving a remainder of 9.
Use 1 as the next digit of our solution. 
Result so far: 47236.1428571
Deduct 21 from 30 and we're left 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.

Step 14:
21 can be fit into 90 4 times, resulting in a remainder of 6.
Use 4 as the next digit of our solution. 
Result so far: 47236.14285714
If we take 84 away from 90, we end up 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.

Our division results in 47236.14285714 with a remaining 6e-09.