We look at the division of 488973 by 21 
We want to divide 488973 by 21.

On to step 1:
The number 21 fits into 4 0 times, leaving a remainder of 4.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we take 0 away from 4, we end up with 4.
Include the next digit (8) from the dividend after 4, then repeat: 48 / 21

Going ahead to step 2:
If we divide 48 by 21, we get 2 and a remainder of 6.
Use 2 as the next digit of our solution. 
Result so far: 2.0
Subtract 42 from 48 to get 6.
Take the next digit (8) from the dividend and append it to 6, then repeat: 68 / 21

Going ahead to step 3:
21 can be fit into 68 3 times, resulting in a remainder of 5.
Write down 3 as next digit of the result. 
Result so far: 23.0
If we take 63 away from 68, we end up with 5.
Take the next digit (9) from the dividend and append it to 5, then repeat: 59 / 21

Let's proceed to step 4:
21 goes into 59 2 times with a remainder of 17.
Record the quotient 2 as the next digit in the result. 
Result so far: 232.0
If we subtract 42 from 59, we get 17.
Bring next digit (7) of the dividend behind the 17 and repeat the process: 177 / 21

On to step 5:
21 can be fit into 177 8 times, resulting in a remainder of 9.
Use 8 as the next digit of our solution. 
Result so far: 2328.0
Subtract 168 from 177 to get 9.
Grab the next digit (3) from the dividend, add it to 9, then carry on: 93 / 21

Step 6:
When dividing 93 by 21, we get 4 with a remainder of 9.
The number 4 becomes the next digit in our result. 
Result so far: 23284.0
Subtract 84 from 93 to 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.

On 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: 23284.4
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.

Moving on to step 8:
When dividing 60 by 21, we get 2 with a remainder of 18.
Use 2 as the next digit of our solution. 
Result so far: 23284.42
Subtract 42 from 60 to 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.

Step 9:
21 can be fit into 180 8 times, resulting in a remainder of 12.
Record the quotient 8 as the next digit in the result. 
Result so far: 23284.428
Subtracting 168 from 180 leaves us 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.

Let's proceed to step 10:
If we divide 120 by 21, we get 5 and a remainder of 15.
The number 5 becomes the next digit in our result. 
Result so far: 23284.4285
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.

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: 23284.42857
Subtracting 147 from 150 leaves us 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.

Step 12:
21 can be fit into 30 1 times, resulting in a remainder of 9.
The number 1 becomes the next digit in our result. 
Result so far: 23284.428571
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.

Step 13:
If we divide 90 by 21, we get 4 and a remainder of 6.
Put 4 as the next digit of the answer. 
Result so far: 23284.4285714
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 14:
If we divide 60 by 21, we get 2 and a remainder of 18.
The number 2 becomes the next digit in our result. 
Result so far: 23284.42857142
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.

Our division results in 23284.42857142 with a remaining 1.8e-08.