53720 ÷ 21 
Let's see how many times 21 fits into 53720.

Advancing to step 1:
If we divide 5 by 21, we get 0 and a remainder of 5.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Deduct 0 from 5 and we're left with 5.
Fetch the next digit (3) from the dividend, attach it to 5 and continue: 53 / 21

Advancing to step 2:
The number 21 fits into 53 2 times, leaving a remainder of 11.
Record the quotient 2 as the next digit in the result. 
Result so far: 2.0
Subtracting 42 from 53 leaves us with 11.
Append the next digit (7) from the dividend to 11 and continue with: 117 / 21

Moving on to step 3:
117 divided by 21 is 5 with a remainder of 12.
Use 5 as the next digit of our solution. 
Result so far: 25.0
Deduct 105 from 117 and we're left with 12.
Take the next digit (2) from the dividend and append it to 12, then repeat: 122 / 21

Moving on to step 4:
122 divided by 21 is 5 with a remainder of 17.
Put 5 as the next digit of the answer. 
Result so far: 255.0
If we take 105 away from 122, we end up with 17.
Grab the next digit (0) from the dividend, add it to 17, then carry on: 170 / 21

Advancing to step 5:
When dividing 170 by 21, we get 8 with a remainder of 2.
The next digit of our result is 8. 
Result so far: 2558.0
The remainder is 2 after subtracting 168 from 170.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Going ahead to step 6:
21 goes into 20 0 times with a remainder of 20.
Write down 0 as next digit of the result. 
Result so far: 2558.0
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 7:
21 goes into 200 9 times with a remainder of 11.
The number 9 becomes the next digit in our result. 
Result so far: 2558.09
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.

Moving on to step 8:
21 goes into 110 5 times with a remainder of 5.
Record the quotient 5 as the next digit in the result. 
Result so far: 2558.095
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.

Going ahead to step 9:
If we divide 50 by 21, we get 2 and a remainder of 8.
Put 2 as the next digit of the answer. 
Result so far: 2558.0952
Subtracting 42 from 50 leaves us 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.

Step 10:
The number 21 fits into 80 3 times, leaving a remainder of 17.
Put 3 as the next digit of the answer. 
Result so far: 2558.09523
Subtracting 63 from 80 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.

Let's proceed to step 11:
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: 2558.095238
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 12:
20 divided by 21 is 0 with a remainder of 20.
Use 0 as the next digit of our solution. 
Result so far: 2558.095238
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.

Step 13:
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: 2558.09523809
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.

The final outcome is 2558.09523809, with a leftover of 1.1e-08.