We're dividing 991996 by 90 
The aim is to understand the frequency of 90 in 991996.

Moving on to step 1:
90 goes into 9 0 times with a remainder of 9.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we subtract 0 from 9, we get 9.
Take the next digit (9) from the dividend and append it to 9, then repeat: 99 / 90

Advancing to step 2:
If we divide 99 by 90, we get 1 and a remainder of 9.
The number 1 becomes the next digit in our result. 
Result so far: 1.0
Subtract 90 from 99 to get 9.
Include the next digit (1) from the dividend after 9, then repeat: 91 / 90

Moving on to step 3:
90 goes into 91 1 times with a remainder of 1.
Write down 1 as next digit of the result. 
Result so far: 11.0
Subtracting 90 from 91 leaves us with 1.
Bring next digit (9) of the dividend behind the 1 and repeat the process: 19 / 90

On to step 4:
When dividing 19 by 90, we get 0 with a remainder of 19.
Put 0 as the next digit of the answer. 
Result so far: 110.0
If we subtract 0 from 19, we get 19.
Include the next digit (9) from the dividend after 19, then repeat: 199 / 90

Moving on to step 5:
90 goes into 199 2 times with a remainder of 19.
The next digit of our result is 2. 
Result so far: 1102.0
If we take 180 away from 199, we end up with 19.
Include the next digit (6) from the dividend after 19, then repeat: 196 / 90

Advancing to step 6:
90 can be fit into 196 2 times, resulting in a remainder of 16.
Write down 2 as next digit of the result. 
Result so far: 11022.0
If we take 180 away from 196, we end up with 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Going ahead to step 7:
160 divided by 90 is 1 with a remainder of 70.
Record the quotient 1 as the next digit in the result. 
Result so far: 11022.1
Subtracting 90 from 160 leaves us with 70.
Since there are no more digits in the dividend, we add a zero to the remainder making it 700, and continue the process.

Step 8:
If we divide 700 by 90, we get 7 and a remainder of 70.
Write down 7 as next digit of the result. 
Result so far: 11022.17
Deduct 630 from 700 and we're left with 70.
Since there are no more digits in the dividend, we add a zero to the remainder making it 700, and continue the process.

Moving on to step 9:
When dividing 700 by 90, we get 7 with a remainder of 70.
Record the quotient 7 as the next digit in the result. 
Result so far: 11022.177
Subtracting 630 from 700 leaves us with 70.
Since there are no more digits in the dividend, we add a zero to the remainder making it 700, and continue the process.

Our division results in 11022.177 with a remaining 0.007.