687075 divided by 90 
The aim is to understand the frequency of 90 in 687075.

Advancing to step 1:
If we divide 6 by 90, we get 0 and a remainder of 6.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtracting 0 from 6 leaves us with 6.
Take the next digit (8) from the dividend and append it to 6, then repeat: 68 / 90

Going ahead to step 2:
If we divide 68 by 90, we get 0 and a remainder of 68.
The next digit of our result is 0. 
Result so far: 0.0
Deduct 0 from 68 and we're left with 68.
Include the next digit (7) from the dividend after 68, then repeat: 687 / 90

Let's proceed to step 3:
If we divide 687 by 90, we get 7 and a remainder of 57.
Write down 7 as next digit of the result. 
Result so far: 7.0
The remainder is 57 after subtracting 630 from 687.
Take the next digit (0) from the dividend and append it to 57, then repeat: 570 / 90

Advancing to step 4:
If we divide 570 by 90, we get 6 and a remainder of 30.
Put 6 as the next digit of the answer. 
Result so far: 76.0
If we take 540 away from 570, we end up with 30.
Bring next digit (7) of the dividend behind the 30 and repeat the process: 307 / 90

Advancing to step 5:
The number 90 fits into 307 3 times, leaving a remainder of 37.
Record the quotient 3 as the next digit in the result. 
Result so far: 763.0
Subtracting 270 from 307 leaves us with 37.
Append the next digit (5) from the dividend to 37 and continue with: 375 / 90

Step 6:
If we divide 375 by 90, we get 4 and a remainder of 15.
Put 4 as the next digit of the answer. 
Result so far: 7634.0
Subtracting 360 from 375 leaves us with 15.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

Going ahead to step 7:
The number 90 fits into 150 1 times, leaving a remainder of 60.
Record the quotient 1 as the next digit in the result. 
Result so far: 7634.1
Subtract 90 from 150 to get 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:
90 goes into 600 6 times with a remainder of 60.
Write down 6 as next digit of the result. 
Result so far: 7634.16
The remainder is 60 after subtracting 540 from 600.
Since there are no more digits in the dividend, we add a zero to the remainder making it 600, and continue the process.

Step 9:
If we divide 600 by 90, we get 6 and a remainder of 60.
Record the quotient 6 as the next digit in the result. 
Result so far: 7634.166
If we take 540 away from 600, we end up 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.

In conclusion, the division gives 7634.166 with a balance of 0.006.