We look at the division of 916850 by 90 
The aim is to understand the frequency of 90 in 916850.

Step 1:
When dividing 9 by 90, we get 0 with a remainder of 9.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we take 0 away from 9, we end up with 9.
Take the next digit (1) from the dividend and append it to 9, then repeat: 91 / 90

Let's proceed to step 2:
90 can be fit into 91 1 times, resulting in a remainder of 1.
The number 1 becomes the next digit in our result. 
Result so far: 1.0
Subtracting 90 from 91 leaves us with 1.
Take the next digit (6) from the dividend and append it to 1, then repeat: 16 / 90

Advancing to step 3:
If we divide 16 by 90, we get 0 and a remainder of 16.
The next digit of our result is 0. 
Result so far: 10.0
If we take 0 away from 16, we end up with 16.
Include the next digit (8) from the dividend after 16, then repeat: 168 / 90

Let's proceed to step 4:
90 can be fit into 168 1 times, resulting in a remainder of 78.
The number 1 becomes the next digit in our result. 
Result so far: 101.0
Subtracting 90 from 168 leaves us with 78.
Grab the next digit (5) from the dividend, add it to 78, then carry on: 785 / 90

Advancing to step 5:
90 can be fit into 785 8 times, resulting in a remainder of 65.
Write down 8 as next digit of the result. 
Result so far: 1018.0
If we take 720 away from 785, we end up with 65.
Bring next digit (0) of the dividend behind the 65 and repeat the process: 650 / 90

Step 6:
When dividing 650 by 90, we get 7 with a remainder of 20.
The number 7 becomes the next digit in our result. 
Result so far: 10187.0
If we take 630 away from 650, we end up with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Going ahead to step 7:
If we divide 200 by 90, we get 2 and a remainder of 20.
The number 2 becomes the next digit in our result. 
Result so far: 10187.2
Deduct 180 from 200 and we're left with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

On to step 8:
When dividing 200 by 90, we get 2 with a remainder of 20.
Put 2 as the next digit of the answer. 
Result so far: 10187.22
Subtracting 180 from 200 leaves us with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

The quotient of the division is 10187.22, and the remainder is 0.02.