We look at the division of 824740 by 21 
We're looking to find how many times 21 goes into 824740.

Moving on to step 1:
If we divide 8 by 21, we get 0 and a remainder of 8.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
The remainder is 8 after subtracting 0 from 8.
Grab the next digit (2) from the dividend, add it to 8, then carry on: 82 / 21

On to step 2:
If we divide 82 by 21, we get 3 and a remainder of 19.
The next digit of our result is 3. 
Result so far: 3.0
Subtract 63 from 82 to get 19.
Grab the next digit (4) from the dividend, add it to 19, then carry on: 194 / 21

Step 3:
21 goes into 194 9 times with a remainder of 5.
Put 9 as the next digit of the answer. 
Result so far: 39.0
Subtracting 189 from 194 leaves us with 5.
Bring next digit (7) of the dividend behind the 5 and repeat the process: 57 / 21

Let's proceed to step 4:
When dividing 57 by 21, we get 2 with a remainder of 15.
Write down 2 as next digit of the result. 
Result so far: 392.0
If we take 42 away from 57, we end up with 15.
Fetch the next digit (4) from the dividend, attach it to 15 and continue: 154 / 21

On to step 5:
When dividing 154 by 21, we get 7 with a remainder of 7.
Put 7 as the next digit of the answer. 
Result so far: 3927.0
Subtracting 147 from 154 leaves us with 7.
Bring next digit (0) of the dividend behind the 7 and repeat the process: 70 / 21

Going ahead to step 6:
When dividing 70 by 21, we get 3 with a remainder of 7.
The number 3 becomes the next digit in our result. 
Result so far: 39273.0
The remainder is 7 after subtracting 63 from 70.
Since there are no more digits in the dividend, we add a zero to the remainder making it 70, and continue the process.

Let's proceed to step 7:
21 goes into 70 3 times with a remainder of 7.
The next digit of our result is 3. 
Result so far: 39273.3
If we take 63 away from 70, we end up with 7.
Since there are no more digits in the dividend, we add a zero to the remainder making it 70, and continue the process.

Advancing to step 8:
The number 21 fits into 70 3 times, leaving a remainder of 7.
Put 3 as the next digit of the answer. 
Result so far: 39273.33
The remainder is 7 after subtracting 63 from 70.
Since there are no more digits in the dividend, we add a zero to the remainder making it 70, and continue the process.

The final outcome is 39273.33, with a leftover of 0.007.