We look at the division of 717580 by 21 
We want to figure out the number of times 717580 can be divided by 21.

Moving on to step 1:
21 can be fit into 7 0 times, resulting in a remainder of 7.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtracting 0 from 7 leaves us with 7.
Take the next digit (1) from the dividend and append it to 7, then repeat: 71 / 21

Going ahead to step 2:
The number 21 fits into 71 3 times, leaving a remainder of 8.
The number 3 becomes the next digit in our result. 
Result so far: 3.0
Deduct 63 from 71 and we're left with 8.
Include the next digit (7) from the dividend after 8, then repeat: 87 / 21

Advancing to step 3:
87 divided by 21 is 4 with a remainder of 3.
Use 4 as the next digit of our solution. 
Result so far: 34.0
Subtract 84 from 87 to get 3.
Append the next digit (5) from the dividend to 3 and continue with: 35 / 21

Step 4:
21 can be fit into 35 1 times, resulting in a remainder of 14.
The number 1 becomes the next digit in our result. 
Result so far: 341.0
Subtracting 21 from 35 leaves us with 14.
Grab the next digit (8) from the dividend, add it to 14, then carry on: 148 / 21

Advancing to step 5:
148 divided by 21 is 7 with a remainder of 1.
Write down 7 as next digit of the result. 
Result so far: 3417.0
The remainder is 1 after subtracting 147 from 148.
Grab the next digit (0) from the dividend, add it to 1, then carry on: 10 / 21

On to step 6:
The number 21 fits into 10 0 times, leaving a remainder of 10.
Use 0 as the next digit of our solution. 
Result so far: 34170.0
The remainder is 10 after subtracting 0 from 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

On to step 7:
100 divided by 21 is 4 with a remainder of 16.
The next digit of our result is 4. 
Result so far: 34170.4
If we subtract 84 from 100, we get 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Let's proceed to step 8:
160 divided by 21 is 7 with a remainder of 13.
The number 7 becomes the next digit in our result. 
Result so far: 34170.47
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.

Going ahead to step 9:
The number 21 fits into 130 6 times, leaving a remainder of 4.
Record the quotient 6 as the next digit in the result. 
Result so far: 34170.476
If we take 126 away from 130, we end up with 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

On to step 10:
The number 21 fits into 40 1 times, leaving a remainder of 19.
The number 1 becomes the next digit in our result. 
Result so far: 34170.4761
If we take 21 away from 40, we end up with 19.
Since there are no more digits in the dividend, we add a zero to the remainder making it 190, and continue the process.

On to step 11:
The number 21 fits into 190 9 times, leaving a remainder of 1.
Use 9 as the next digit of our solution. 
Result so far: 34170.47619
Deduct 189 from 190 and we're left with 1.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

On to step 12:
21 goes into 10 0 times with a remainder of 10.
Record the quotient 0 as the next digit in the result. 
Result so far: 34170.47619
Subtracting 0 from 10 leaves us 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.

Going ahead to step 13:
When dividing 100 by 21, we get 4 with a remainder of 16.
The next digit of our result is 4. 
Result so far: 34170.4761904
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.

Advancing to step 14:
21 goes into 160 7 times with a remainder of 13.
Record the quotient 7 as the next digit in the result. 
Result so far: 34170.47619047
The remainder is 13 after subtracting 147 from 160.
Since there are no more digits in the dividend, we add a zero to the remainder making it 130, and continue the process.

Our division results in 34170.47619047 with a remaining 1.3e-08.