We're dividing 21089450 by 457 
Let's see how many times 457 fits into 21089450.

Going ahead to step 1:
The number 457 fits into 2 0 times, leaving a remainder of 2.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we subtract 0 from 2, we get 2.
Include the next digit (1) from the dividend after 2, then repeat: 21 / 457

Going ahead to step 2:
When dividing 21 by 457, we get 0 with a remainder of 21.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 21, we end up with 21.
Take the next digit (0) from the dividend and append it to 21, then repeat: 210 / 457

On to step 3:
When dividing 210 by 457, we get 0 with a remainder of 210.
The next digit of our result is 0. 
Result so far: 0.0
Subtracting 0 from 210 leaves us with 210.
Append the next digit (8) from the dividend to 210 and continue with: 2108 / 457

Going ahead to step 4:
The number 457 fits into 2108 4 times, leaving a remainder of 280.
Use 4 as the next digit of our solution. 
Result so far: 4.0
If we subtract 1828 from 2108, we get 280.
Include the next digit (9) from the dividend after 280, then repeat: 2809 / 457

Moving on to step 5:
457 goes into 2809 6 times with a remainder of 67.
The number 6 becomes the next digit in our result. 
Result so far: 46.0
Subtract 2742 from 2809 to get 67.
Take the next digit (4) from the dividend and append it to 67, then repeat: 674 / 457

Let's proceed to step 6:
674 divided by 457 is 1 with a remainder of 217.
Write down 1 as next digit of the result. 
Result so far: 461.0
If we take 457 away from 674, we end up with 217.
Bring next digit (5) of the dividend behind the 217 and repeat the process: 2175 / 457

Let's proceed to step 7:
2175 divided by 457 is 4 with a remainder of 347.
Put 4 as the next digit of the answer. 
Result so far: 4614.0
Subtract 1828 from 2175 to get 347.
Bring next digit (0) of the dividend behind the 347 and repeat the process: 3470 / 457

Advancing to step 8:
The number 457 fits into 3470 7 times, leaving a remainder of 271.
Record the quotient 7 as the next digit in the result. 
Result so far: 46147.0
Deduct 3199 from 3470 and we're left with 271.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2710, and continue the process.

Step 9:
If we divide 2710 by 457, we get 5 and a remainder of 425.
Write down 5 as next digit of the result. 
Result so far: 46147.5
Subtracting 2285 from 2710 leaves us with 425.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4250, and continue the process.

On to step 10:
457 goes into 4250 9 times with a remainder of 137.
Write down 9 as next digit of the result. 
Result so far: 46147.59
If we subtract 4113 from 4250, we get 137.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1370, and continue the process.

On to step 11:
457 can be fit into 1370 2 times, resulting in a remainder of 456.
Put 2 as the next digit of the answer. 
Result so far: 46147.592
If we take 914 away from 1370, we end up with 456.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4560, and continue the process.

Moving on to step 12:
457 can be fit into 4560 9 times, resulting in a remainder of 447.
Put 9 as the next digit of the answer. 
Result so far: 46147.5929
If we take 4113 away from 4560, we end up with 447.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4470, and continue the process.

Moving on to step 13:
The number 457 fits into 4470 9 times, leaving a remainder of 357.
Record the quotient 9 as the next digit in the result. 
Result so far: 46147.59299
Subtracting 4113 from 4470 leaves us with 357.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3570, and continue the process.

After the division, we end up with 46147.59299 and a remainder of 0.000357.