We're dividing 815729 by 20 
We're looking to find how many times 20 goes into 815729.

Step 1:
If we divide 8 by 20, we get 0 and a remainder of 8.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtracting 0 from 8 leaves us with 8.
Grab the next digit (1) from the dividend, add it to 8, then carry on: 81 / 20

On to step 2:
20 goes into 81 4 times with a remainder of 1.
Write down 4 as next digit of the result. 
Result so far: 4.0
Subtract 80 from 81 to get 1.
Append the next digit (5) from the dividend to 1 and continue with: 15 / 20

Let's proceed to step 3:
20 goes into 15 0 times with a remainder of 15.
Write down 0 as next digit of the result. 
Result so far: 40.0
Subtracting 0 from 15 leaves us with 15.
Include the next digit (7) from the dividend after 15, then repeat: 157 / 20

Let's proceed to step 4:
20 can be fit into 157 7 times, resulting in a remainder of 17.
Use 7 as the next digit of our solution. 
Result so far: 407.0
If we subtract 140 from 157, we get 17.
Grab the next digit (2) from the dividend, add it to 17, then carry on: 172 / 20

Going ahead to step 5:
The number 20 fits into 172 8 times, leaving a remainder of 12.
Put 8 as the next digit of the answer. 
Result so far: 4078.0
The remainder is 12 after subtracting 160 from 172.
Grab the next digit (9) from the dividend, add it to 12, then carry on: 129 / 20

Going ahead to step 6:
20 goes into 129 6 times with a remainder of 9.
The next digit of our result is 6. 
Result so far: 40786.0
Subtracting 120 from 129 leaves us with 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

Advancing to step 7:
90 divided by 20 is 4 with a remainder of 10.
Use 4 as the next digit of our solution. 
Result so far: 40786.4
Subtracting 80 from 90 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.

Advancing to step 8:
The number 20 fits into 100 5 times, leaving a remainder of 0.
Put 5 as the next digit of the answer. 
Result so far: 40786.45
Subtracting 100 from 100 leaves us with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Let's proceed to step 9:
20 can be fit into 0 0 times, resulting in a remainder of 0.
Record the quotient 0 as the next digit in the result. 
Result so far: 40786.45
If we subtract 0 from 0, we get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Going ahead to step 10:
When dividing 0 by 20, we get 0 with a remainder of 0.
Record the quotient 0 as the next digit in the result. 
Result so far: 40786.45
Deduct 0 from 0 and we're left with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

The final outcome is 40786.45, with a leftover of 0.0.