We look at the division of 957830 by 90 
The aim is to understand the frequency of 90 in 957830.

Advancing to step 1:
If we divide 9 by 90, we get 0 and a remainder of 9.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we subtract 0 from 9, we get 9.
Include the next digit (5) from the dividend after 9, then repeat: 95 / 90

Going ahead to step 2:
90 can be fit into 95 1 times, resulting in a remainder of 5.
The number 1 becomes the next digit in our result. 
Result so far: 1.0
Subtract 90 from 95 to get 5.
Fetch the next digit (7) from the dividend, attach it to 5 and continue: 57 / 90

Moving on to step 3:
90 goes into 57 0 times with a remainder of 57.
Record the quotient 0 as the next digit in the result. 
Result so far: 10.0
Subtract 0 from 57 to get 57.
Include the next digit (8) from the dividend after 57, then repeat: 578 / 90

Let's proceed to step 4:
When dividing 578 by 90, we get 6 with a remainder of 38.
Use 6 as the next digit of our solution. 
Result so far: 106.0
The remainder is 38 after subtracting 540 from 578.
Include the next digit (3) from the dividend after 38, then repeat: 383 / 90

Moving on to step 5:
383 divided by 90 is 4 with a remainder of 23.
Write down 4 as next digit of the result. 
Result so far: 1064.0
Deduct 360 from 383 and we're left with 23.
Fetch the next digit (0) from the dividend, attach it to 23 and continue: 230 / 90

Moving on to step 6:
90 can be fit into 230 2 times, resulting in a remainder of 50.
The next digit of our result is 2. 
Result so far: 10642.0
If we subtract 180 from 230, we get 50.
Since there are no more digits in the dividend, we add a zero to the remainder making it 500, and continue the process.

On to step 7:
The number 90 fits into 500 5 times, leaving a remainder of 50.
The number 5 becomes the next digit in our result. 
Result so far: 10642.5
Subtract 450 from 500 to get 50.
Since there are no more digits in the dividend, we add a zero to the remainder making it 500, and continue the process.

On to step 8:
90 can be fit into 500 5 times, resulting in a remainder of 50.
Record the quotient 5 as the next digit in the result. 
Result so far: 10642.55
Subtract 450 from 500 to get 50.
Since there are no more digits in the dividend, we add a zero to the remainder making it 500, and continue the process.

The quotient of the division is 10642.55, and the remainder is 0.05.