We look at the division of 418456 by 21 
We're looking to find how many times 21 goes into 418456.

Going ahead to step 1:
4 divided by 21 is 0 with a remainder of 4.
Write down 0 as next digit of the result. 
Result so far: 0.0
The remainder is 4 after subtracting 0 from 4.
Grab the next digit (1) from the dividend, add it to 4, then carry on: 41 / 21

Going ahead to step 2:
21 goes into 41 1 times with a remainder of 20.
Use 1 as the next digit of our solution. 
Result so far: 1.0
Subtract 21 from 41 to get 20.
Include the next digit (8) from the dividend after 20, then repeat: 208 / 21

On to step 3:
The number 21 fits into 208 9 times, leaving a remainder of 19.
Record the quotient 9 as the next digit in the result. 
Result so far: 19.0
Subtracting 189 from 208 leaves us with 19.
Bring next digit (4) of the dividend behind the 19 and repeat the process: 194 / 21

Let's proceed to step 4:
When dividing 194 by 21, we get 9 with a remainder of 5.
The next digit of our result is 9. 
Result so far: 199.0
If we subtract 189 from 194, we get 5.
Append the next digit (5) from the dividend to 5 and continue with: 55 / 21

Moving on to step 5:
55 divided by 21 is 2 with a remainder of 13.
The number 2 becomes the next digit in our result. 
Result so far: 1992.0
If we take 42 away from 55, we end up with 13.
Bring next digit (6) of the dividend behind the 13 and repeat the process: 136 / 21

Moving on to step 6:
21 goes into 136 6 times with a remainder of 10.
Record the quotient 6 as the next digit in the result. 
Result so far: 19926.0
If we take 126 away from 136, we end up with 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Advancing to step 7:
21 can be fit into 100 4 times, resulting in a remainder of 16.
Record the quotient 4 as the next digit in the result. 
Result so far: 19926.4
The remainder is 16 after subtracting 84 from 100.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

On to step 8:
When dividing 160 by 21, we get 7 with a remainder of 13.
Put 7 as the next digit of the answer. 
Result so far: 19926.47
Subtract 147 from 160 to get 13.
Since there are no more digits in the dividend, we add a zero to the remainder making it 130, and continue the process.

Let's proceed to step 9:
21 goes into 130 6 times with a remainder of 4.
Use 6 as the next digit of our solution. 
Result so far: 19926.476
Subtract 126 from 130 to get 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Step 10:
21 goes into 40 1 times with a remainder of 19.
The next digit of our result is 1. 
Result so far: 19926.4761
The remainder is 19 after subtracting 21 from 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 190, and continue the process.

Going ahead to step 11:
21 can be fit into 190 9 times, resulting in a remainder of 1.
Put 9 as the next digit of the answer. 
Result so far: 19926.47619
Subtract 189 from 190 to get 1.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

Advancing to step 12:
21 goes into 10 0 times with a remainder of 10.
Put 0 as the next digit of the answer. 
Result so far: 19926.47619
Subtract 0 from 10 to get 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Let's proceed to step 13:
The number 21 fits into 100 4 times, leaving a remainder of 16.
Write down 4 as next digit of the result. 
Result so far: 19926.4761904
Deduct 84 from 100 and we're left with 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Advancing to step 14:
21 goes into 160 7 times with a remainder of 13.
Write down 7 as next digit of the result. 
Result so far: 19926.47619047
If we subtract 147 from 160, we get 13.
Since there are no more digits in the dividend, we add a zero to the remainder making it 130, and continue the process.

In conclusion, the division gives 19926.47619047 with a balance of 1.3e-08.