20789 ÷ 90 
We want to divide 20789 by 90.

Going ahead to step 1:
When dividing 2 by 90, we get 0 with a remainder of 2.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
The remainder is 2 after subtracting 0 from 2.
Include the next digit (0) from the dividend after 2, then repeat: 20 / 90

Moving on to step 2:
90 can be fit into 20 0 times, resulting in a remainder of 20.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Deduct 0 from 20 and we're left with 20.
Grab the next digit (7) from the dividend, add it to 20, then carry on: 207 / 90

Advancing to step 3:
If we divide 207 by 90, we get 2 and a remainder of 27.
Put 2 as the next digit of the answer. 
Result so far: 2.0
Subtract 180 from 207 to get 27.
Take the next digit (8) from the dividend and append it to 27, then repeat: 278 / 90

Advancing to step 4:
90 can be fit into 278 3 times, resulting in a remainder of 8.
Record the quotient 3 as the next digit in the result. 
Result so far: 23.0
If we subtract 270 from 278, we get 8.
Take the next digit (9) from the dividend and append it to 8, then repeat: 89 / 90

On to step 5:
90 can be fit into 89 0 times, resulting in a remainder of 89.
Use 0 as the next digit of our solution. 
Result so far: 230.0
Subtracting 0 from 89 leaves us with 89.
Since there are no more digits in the dividend, we add a zero to the remainder making it 890, and continue the process.

Advancing to step 6:
890 divided by 90 is 9 with a remainder of 80.
The next digit of our result is 9. 
Result so far: 230.9
If we subtract 810 from 890, we get 80.
Since there are no more digits in the dividend, we add a zero to the remainder making it 800, and continue the process.

On to step 7:
90 can be fit into 800 8 times, resulting in a remainder of 80.
Record the quotient 8 as the next digit in the result. 
Result so far: 230.98
Subtract 720 from 800 to get 80.
Since there are no more digits in the dividend, we add a zero to the remainder making it 800, and continue the process.

Advancing to step 8:
90 goes into 800 8 times with a remainder of 80.
The number 8 becomes the next digit in our result. 
Result so far: 230.988
If we take 720 away from 800, we end up with 80.
Since there are no more digits in the dividend, we add a zero to the remainder making it 800, and continue the process.

After the division, we end up with 230.988 and a remainder of 0.008.