957669 ÷ 90 
The aim is to understand the frequency of 90 in 957669.

Step 1:
9 divided by 90 is 0 with a remainder of 9.
The next digit of our result is 0. 
Result so far: 0.0
If we take 0 away from 9, we end up with 9.
Take the next digit (5) from the dividend and append it to 9, then repeat: 95 / 90

Going ahead to step 2:
90 goes into 95 1 times with a remainder of 5.
Use 1 as the next digit of our solution. 
Result so far: 1.0
If we take 90 away from 95, we end up with 5.
Grab the next digit (7) from the dividend, add it to 5, then carry on: 57 / 90

On to step 3:
90 can be fit into 57 0 times, resulting in a remainder of 57.
Record the quotient 0 as the next digit in the result. 
Result so far: 10.0
The remainder is 57 after subtracting 0 from 57.
Grab the next digit (6) from the dividend, add it to 57, then carry on: 576 / 90

Advancing to step 4:
The number 90 fits into 576 6 times, leaving a remainder of 36.
The next digit of our result is 6. 
Result so far: 106.0
Deduct 540 from 576 and we're left with 36.
Append the next digit (6) from the dividend to 36 and continue with: 366 / 90

Moving on to step 5:
366 divided by 90 is 4 with a remainder of 6.
The number 4 becomes the next digit in our result. 
Result so far: 1064.0
Deduct 360 from 366 and we're left with 6.
Append the next digit (9) from the dividend to 6 and continue with: 69 / 90

Step 6:
69 divided by 90 is 0 with a remainder of 69.
Record the quotient 0 as the next digit in the result. 
Result so far: 10640.0
Subtracting 0 from 69 leaves us with 69.
Since there are no more digits in the dividend, we add a zero to the remainder making it 690, and continue the process.

Let's proceed to step 7:
90 can be fit into 690 7 times, resulting in a remainder of 60.
The next digit of our result is 7. 
Result so far: 10640.7
Subtracting 630 from 690 leaves us with 60.
Since there are no more digits in the dividend, we add a zero to the remainder making it 600, and continue the process.

Advancing to step 8:
600 divided by 90 is 6 with a remainder of 60.
The number 6 becomes the next digit in our result. 
Result so far: 10640.76
Deduct 540 from 600 and we're left with 60.
Since there are no more digits in the dividend, we add a zero to the remainder making it 600, and continue the process.

Moving on to step 9:
600 divided by 90 is 6 with a remainder of 60.
Write down 6 as next digit of the result. 
Result so far: 10640.766
Subtracting 540 from 600 leaves us with 60.
Since there are no more digits in the dividend, we add a zero to the remainder making it 600, and continue the process.

After the division, we end up with 10640.766 and a remainder of 0.006.