We look at the division of 815890 by 20 
We want to figure out the number of times 815890 can be divided by 20.

Moving on to step 1:
When dividing 8 by 20, we get 0 with a remainder of 8.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we take 0 away from 8, we end up with 8.
Fetch the next digit (1) from the dividend, attach it to 8 and continue: 81 / 20

Going ahead to step 2:
When dividing 81 by 20, we get 4 with a remainder of 1.
Use 4 as the next digit of our solution. 
Result so far: 4.0
If we subtract 80 from 81, we get 1.
Bring next digit (5) of the dividend behind the 1 and repeat the process: 15 / 20

Let's proceed to step 3:
The number 20 fits into 15 0 times, leaving a remainder of 15.
Use 0 as the next digit of our solution. 
Result so far: 40.0
The remainder is 15 after subtracting 0 from 15.
Include the next digit (8) from the dividend after 15, then repeat: 158 / 20

Advancing to step 4:
The number 20 fits into 158 7 times, leaving a remainder of 18.
Use 7 as the next digit of our solution. 
Result so far: 407.0
The remainder is 18 after subtracting 140 from 158.
Fetch the next digit (9) from the dividend, attach it to 18 and continue: 189 / 20

Let's proceed to step 5:
When dividing 189 by 20, we get 9 with a remainder of 9.
Record the quotient 9 as the next digit in the result. 
Result so far: 4079.0
Deduct 180 from 189 and we're left with 9.
Append the next digit (0) from the dividend to 9 and continue with: 90 / 20

Let's proceed to step 6:
When dividing 90 by 20, we get 4 with a remainder of 10.
Write down 4 as next digit of the result. 
Result so far: 40794.0
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.

Going ahead to step 7:
The number 20 fits into 100 5 times, leaving a remainder of 0.
Record the quotient 5 as the next digit in the result. 
Result so far: 40794.5
Deduct 100 from 100 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.

Moving on to step 8:
20 can be fit into 0 0 times, resulting in a remainder of 0.
Write down 0 as next digit of the result. 
Result so far: 40794.5
If we take 0 away from 0, we end up 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.

On to step 9:
If we divide 0 by 20, we get 0 and a remainder of 0.
The next digit of our result is 0. 
Result so far: 40794.5
Subtracting 0 from 0 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.

The final outcome is 40794.5, with a leftover of 0.0.