We're dividing 418490 by 21 
Our goal is to divide 418490 by 21.

Advancing to step 1:
21 goes into 4 0 times with a remainder of 4.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we take 0 away from 4, we end up with 4.
Fetch the next digit (1) from the dividend, attach it to 4 and continue: 41 / 21

On to step 2:
The number 21 fits into 41 1 times, leaving a remainder of 20.
Put 1 as the next digit of the answer. 
Result so far: 1.0
If we take 21 away from 41, we end up with 20.
Take the next digit (8) from the dividend and append it to 20, then repeat: 208 / 21

Advancing to step 3:
208 divided by 21 is 9 with a remainder of 19.
Record the quotient 9 as the next digit in the result. 
Result so far: 19.0
The remainder is 19 after subtracting 189 from 208.
Take the next digit (4) from the dividend and append it to 19, then repeat: 194 / 21

Moving on to step 4:
When dividing 194 by 21, we get 9 with a remainder of 5.
The number 9 becomes the next digit in our result. 
Result so far: 199.0
If we subtract 189 from 194, we get 5.
Bring next digit (9) of the dividend behind the 5 and repeat the process: 59 / 21

Going ahead to step 5:
The number 21 fits into 59 2 times, leaving a remainder of 17.
Record the quotient 2 as the next digit in the result. 
Result so far: 1992.0
Subtracting 42 from 59 leaves us with 17.
Append the next digit (0) from the dividend to 17 and continue with: 170 / 21

Let's proceed to step 6:
170 divided by 21 is 8 with a remainder of 2.
Put 8 as the next digit of the answer. 
Result so far: 19928.0
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.

On to step 7:
When dividing 20 by 21, we get 0 with a remainder of 20.
Record the quotient 0 as the next digit in the result. 
Result so far: 19928.0
Deduct 0 from 20 and we're left 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.

Step 8:
When dividing 200 by 21, we get 9 with a remainder of 11.
Use 9 as the next digit of our solution. 
Result so far: 19928.09
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.

Step 9:
21 can be fit into 110 5 times, resulting in a remainder of 5.
Write down 5 as next digit of the result. 
Result so far: 19928.095
Subtract 105 from 110 to get 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Step 10:
21 goes into 50 2 times with a remainder of 8.
The next digit of our result is 2. 
Result so far: 19928.0952
Subtract 42 from 50 to get 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Let's proceed to step 11:
21 can be fit into 80 3 times, resulting in a remainder of 17.
The number 3 becomes the next digit in our result. 
Result so far: 19928.09523
Subtract 63 from 80 to get 17.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

Advancing to step 12:
21 can be fit into 170 8 times, resulting in a remainder of 2.
Use 8 as the next digit of our solution. 
Result so far: 19928.095238
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.

Moving on to step 13:
The number 21 fits into 20 0 times, leaving a remainder of 20.
Use 0 as the next digit of our solution. 
Result so far: 19928.095238
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 can be fit into 200 9 times, resulting in a remainder of 11.
The next digit of our result is 9. 
Result so far: 19928.09523809
If we subtract 189 from 200, we get 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

After the division, we end up with 19928.09523809 and a remainder of 1.1e-08.