88231 divided by 90 
The aim is to understand the frequency of 90 in 88231.

On to step 1:
If we divide 8 by 90, we get 0 and a remainder of 8.
Put 0 as the next digit of the answer. 
Result so far: 0.0
The remainder is 8 after subtracting 0 from 8.
Bring next digit (8) of the dividend behind the 8 and repeat the process: 88 / 90

Going ahead to step 2:
88 divided by 90 is 0 with a remainder of 88.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 88 to get 88.
Fetch the next digit (2) from the dividend, attach it to 88 and continue: 882 / 90

On to step 3:
882 divided by 90 is 9 with a remainder of 72.
Use 9 as the next digit of our solution. 
Result so far: 9.0
Subtracting 810 from 882 leaves us with 72.
Include the next digit (3) from the dividend after 72, then repeat: 723 / 90

Let's proceed to step 4:
90 goes into 723 8 times with a remainder of 3.
The next digit of our result is 8. 
Result so far: 98.0
Subtracting 720 from 723 leaves us with 3.
Grab the next digit (1) from the dividend, add it to 3, then carry on: 31 / 90

Going ahead to step 5:
90 goes into 31 0 times with a remainder of 31.
The next digit of our result is 0. 
Result so far: 980.0
The remainder is 31 after subtracting 0 from 31.
Since there are no more digits in the dividend, we add a zero to the remainder making it 310, and continue the process.

On to step 6:
If we divide 310 by 90, we get 3 and a remainder of 40.
Use 3 as the next digit of our solution. 
Result so far: 980.3
The remainder is 40 after subtracting 270 from 310.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

Let's proceed to step 7:
The number 90 fits into 400 4 times, leaving a remainder of 40.
The next digit of our result is 4. 
Result so far: 980.34
Deduct 360 from 400 and we're left with 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

On to step 8:
90 can be fit into 400 4 times, resulting in a remainder of 40.
Use 4 as the next digit of our solution. 
Result so far: 980.344
If we take 360 away from 400, we end up with 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

The final outcome is 980.344, with a leftover of 0.004.