79807 ÷ 21 
We're looking to find how many times 21 goes into 79807.

Step 1:
21 can be fit into 7 0 times, resulting in a remainder of 7.
The next digit of our result is 0. 
Result so far: 0.0
If we subtract 0 from 7, we get 7.
Take the next digit (9) from the dividend and append it to 7, then repeat: 79 / 21

Let's proceed to step 2:
When dividing 79 by 21, we get 3 with a remainder of 16.
Use 3 as the next digit of our solution. 
Result so far: 3.0
Deduct 63 from 79 and we're left with 16.
Take the next digit (8) from the dividend and append it to 16, then repeat: 168 / 21

On to step 3:
21 can be fit into 168 8 times, resulting in a remainder of 0.
Put 8 as the next digit of the answer. 
Result so far: 38.0
If we subtract 168 from 168, we get 0.
Fetch the next digit (0) from the dividend, attach it to 0 and continue: 0 / 21

On to step 4:
If we divide 0 by 21, we get 0 and a remainder of 0.
Put 0 as the next digit of the answer. 
Result so far: 380.0
If we subtract 0 from 0, we get 0.
Bring next digit (7) of the dividend behind the 0 and repeat the process: 7 / 21

Step 5:
7 divided by 21 is 0 with a remainder of 7.
Write down 0 as next digit of the result. 
Result so far: 3800.0
The remainder is 7 after subtracting 0 from 7.
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 6:
If we divide 70 by 21, we get 3 and a remainder of 7.
Put 3 as the next digit of the answer. 
Result so far: 3800.3
Subtracting 63 from 70 leaves us 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.

Moving on to step 7:
21 can be fit into 70 3 times, resulting in a remainder of 7.
The next digit of our result is 3. 
Result so far: 3800.33
Deduct 63 from 70 and we're left 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.

The final outcome is 3800.33, with a leftover of 0.007.