907028 ÷ 21 
We're looking to find how many times 21 goes into 907028.

Moving on to step 1:
If we divide 9 by 21, we get 0 and a remainder of 9.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 9, we end up with 9.
Fetch the next digit (0) from the dividend, attach it to 9 and continue: 90 / 21

Step 2:
The number 21 fits into 90 4 times, leaving a remainder of 6.
Use 4 as the next digit of our solution. 
Result so far: 4.0
Deduct 84 from 90 and we're left with 6.
Include the next digit (7) from the dividend after 6, then repeat: 67 / 21

Step 3:
If we divide 67 by 21, we get 3 and a remainder of 4.
The next digit of our result is 3. 
Result so far: 43.0
If we take 63 away from 67, we end up with 4.
Grab the next digit (0) from the dividend, add it to 4, then carry on: 40 / 21

Step 4:
When dividing 40 by 21, we get 1 with a remainder of 19.
The number 1 becomes the next digit in our result. 
Result so far: 431.0
Subtracting 21 from 40 leaves us with 19.
Grab the next digit (2) from the dividend, add it to 19, then carry on: 192 / 21

Moving on to step 5:
The number 21 fits into 192 9 times, leaving a remainder of 3.
The number 9 becomes the next digit in our result. 
Result so far: 4319.0
Subtracting 189 from 192 leaves us with 3.
Include the next digit (8) from the dividend after 3, then repeat: 38 / 21

On to step 6:
38 divided by 21 is 1 with a remainder of 17.
Put 1 as the next digit of the answer. 
Result so far: 43191.0
If we take 21 away from 38, we end up 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.

Going ahead to step 7:
When dividing 170 by 21, we get 8 with a remainder of 2.
Write down 8 as next digit of the result. 
Result so far: 43191.8
If we subtract 168 from 170, we 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.

Advancing to step 8:
The number 21 fits into 20 0 times, leaving a remainder of 20.
Put 0 as the next digit of the answer. 
Result so far: 43191.8
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.

Going ahead to step 9:
When dividing 200 by 21, we get 9 with a remainder of 11.
Record the quotient 9 as the next digit in the result. 
Result so far: 43191.809
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.

Going ahead to step 10:
When dividing 110 by 21, we get 5 with a remainder of 5.
Use 5 as the next digit of our solution. 
Result so far: 43191.8095
Deduct 105 from 110 and we're left 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.

Moving on to step 11:
The number 21 fits into 50 2 times, leaving a remainder of 8.
Record the quotient 2 as the next digit in the result. 
Result so far: 43191.80952
Deduct 42 from 50 and we're left 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 12:
When dividing 80 by 21, we get 3 with a remainder of 17.
Put 3 as the next digit of the answer. 
Result so far: 43191.809523
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.

Let's proceed to step 13:
The number 21 fits into 170 8 times, leaving a remainder of 2.
The next digit of our result is 8. 
Result so far: 43191.8095238
If we subtract 168 from 170, we 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.

Moving on to step 14:
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: 43191.8095238
Subtract 0 from 20 to 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.

The final result is 43191.8095238 with a remainder of 2e-08.