140520 divided by 21 
We want to divide 140520 by 21.

Step 1:
1 divided by 21 is 0 with a remainder of 1.
The next digit of our result is 0. 
Result so far: 0.0
Subtracting 0 from 1 leaves us with 1.
Fetch the next digit (4) from the dividend, attach it to 1 and continue: 14 / 21

Step 2:
21 goes into 14 0 times with a remainder of 14.
Write down 0 as next digit of the result. 
Result so far: 0.0
Deduct 0 from 14 and we're left with 14.
Fetch the next digit (0) from the dividend, attach it to 14 and continue: 140 / 21

Moving on to step 3:
21 can be fit into 140 6 times, resulting in a remainder of 14.
The next digit of our result is 6. 
Result so far: 6.0
If we take 126 away from 140, we end up with 14.
Append the next digit (5) from the dividend to 14 and continue with: 145 / 21

On to step 4:
21 can be fit into 145 6 times, resulting in a remainder of 19.
Put 6 as the next digit of the answer. 
Result so far: 66.0
The remainder is 19 after subtracting 126 from 145.
Append the next digit (2) from the dividend to 19 and continue with: 192 / 21

Going ahead to step 5:
21 goes into 192 9 times with a remainder of 3.
Use 9 as the next digit of our solution. 
Result so far: 669.0
Subtracting 189 from 192 leaves us with 3.
Bring next digit (0) of the dividend behind the 3 and repeat the process: 30 / 21

Going ahead to step 6:
If we divide 30 by 21, we get 1 and a remainder of 9.
Use 1 as the next digit of our solution. 
Result so far: 6691.0
If we take 21 away from 30, we end up 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.

Going ahead to step 7:
If we divide 90 by 21, we get 4 and a remainder of 6.
Record the quotient 4 as the next digit in the result. 
Result so far: 6691.4
The remainder is 6 after subtracting 84 from 90.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

Let's proceed to step 8:
60 divided by 21 is 2 with a remainder of 18.
Record the quotient 2 as the next digit in the result. 
Result so far: 6691.42
If we take 42 away from 60, we end up with 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

On to step 9:
If we divide 180 by 21, we get 8 and a remainder of 12.
The next digit of our result is 8. 
Result so far: 6691.428
If we take 168 away from 180, we end up with 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Moving on to step 10:
When dividing 120 by 21, we get 5 with a remainder of 15.
The next digit of our result is 5. 
Result so far: 6691.4285
Deduct 105 from 120 and we're left with 15.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

Moving on to step 11:
21 can be fit into 150 7 times, resulting in a remainder of 3.
Use 7 as the next digit of our solution. 
Result so far: 6691.42857
If we subtract 147 from 150, 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.

Going ahead to step 12:
If we divide 30 by 21, we get 1 and a remainder of 9.
Put 1 as the next digit of the answer. 
Result so far: 6691.428571
The remainder is 9 after subtracting 21 from 30.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

Let's proceed to step 13:
21 goes into 90 4 times with a remainder of 6.
Use 4 as the next digit of our solution. 
Result so far: 6691.4285714
Deduct 84 from 90 and we're left 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.

Let's proceed to step 14:
60 divided by 21 is 2 with a remainder of 18.
The number 2 becomes the next digit in our result. 
Result so far: 6691.42857142
If we subtract 42 from 60, we get 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

After the division, we end up with 6691.42857142 and a remainder of 1.8e-08.