We're dividing 823474 by 90 
The aim is to understand the frequency of 90 in 823474.

Moving on to step 1:
When dividing 8 by 90, we get 0 with a remainder of 8.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we subtract 0 from 8, we get 8.
Grab the next digit (2) from the dividend, add it to 8, then carry on: 82 / 90

On to step 2:
82 divided by 90 is 0 with a remainder of 82.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 82 to get 82.
Fetch the next digit (3) from the dividend, attach it to 82 and continue: 823 / 90

On to step 3:
The number 90 fits into 823 9 times, leaving a remainder of 13.
The number 9 becomes the next digit in our result. 
Result so far: 9.0
Subtracting 810 from 823 leaves us with 13.
Include the next digit (4) from the dividend after 13, then repeat: 134 / 90

Let's proceed to step 4:
If we divide 134 by 90, we get 1 and a remainder of 44.
Write down 1 as next digit of the result. 
Result so far: 91.0
The remainder is 44 after subtracting 90 from 134.
Fetch the next digit (7) from the dividend, attach it to 44 and continue: 447 / 90

On to step 5:
If we divide 447 by 90, we get 4 and a remainder of 87.
Record the quotient 4 as the next digit in the result. 
Result so far: 914.0
Deduct 360 from 447 and we're left with 87.
Take the next digit (4) from the dividend and append it to 87, then repeat: 874 / 90

Advancing to step 6:
90 goes into 874 9 times with a remainder of 64.
Use 9 as the next digit of our solution. 
Result so far: 9149.0
Subtract 810 from 874 to get 64.
Since there are no more digits in the dividend, we add a zero to the remainder making it 640, and continue the process.

Step 7:
If we divide 640 by 90, we get 7 and a remainder of 10.
Write down 7 as next digit of the result. 
Result so far: 9149.7
If we subtract 630 from 640, we get 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 8:
100 divided by 90 is 1 with a remainder of 10.
Record the quotient 1 as the next digit in the result. 
Result so far: 9149.71
If we subtract 90 from 100, we get 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 9:
When dividing 100 by 90, we get 1 with a remainder of 10.
The number 1 becomes the next digit in our result. 
Result so far: 9149.711
Subtracting 90 from 100 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.

Our division results in 9149.711 with a remaining 0.001.