Let's divide 685781 by 90
The aim is to understand the frequency of 90 in 685781.

On to step 1:
6 divided by 90 is 0 with a remainder of 6.
Use 0 as the next digit of our solution. 
Result so far: 0.0
The remainder is 6 after subtracting 0 from 6.
Fetch the next digit (8) from the dividend, attach it to 6 and continue: 68 / 90

On to step 2:
When dividing 68 by 90, we get 0 with a remainder of 68.
The next digit of our result is 0. 
Result so far: 0.0
Subtract 0 from 68 to get 68.
Include the next digit (5) from the dividend after 68, then repeat: 685 / 90

Let's proceed to step 3:
When dividing 685 by 90, we get 7 with a remainder of 55.
Use 7 as the next digit of our solution. 
Result so far: 7.0
The remainder is 55 after subtracting 630 from 685.
Include the next digit (7) from the dividend after 55, then repeat: 557 / 90

On to step 4:
90 goes into 557 6 times with a remainder of 17.
Record the quotient 6 as the next digit in the result. 
Result so far: 76.0
If we take 540 away from 557, we end up with 17.
Bring next digit (8) of the dividend behind the 17 and repeat the process: 178 / 90

Going ahead to step 5:
If we divide 178 by 90, we get 1 and a remainder of 88.
Use 1 as the next digit of our solution. 
Result so far: 761.0
Deduct 90 from 178 and we're left with 88.
Bring next digit (1) of the dividend behind the 88 and repeat the process: 881 / 90

Going ahead to step 6:
When dividing 881 by 90, we get 9 with a remainder of 71.
The number 9 becomes the next digit in our result. 
Result so far: 7619.0
Subtract 810 from 881 to get 71.
Since there are no more digits in the dividend, we add a zero to the remainder making it 710, and continue the process.

Let's proceed to step 7:
90 can be fit into 710 7 times, resulting in a remainder of 80.
The number 7 becomes the next digit in our result. 
Result so far: 7619.7
Subtract 630 from 710 to get 80.
Since there are no more digits in the dividend, we add a zero to the remainder making it 800, and continue the process.

Moving on to step 8:
800 divided by 90 is 8 with a remainder of 80.
Record the quotient 8 as the next digit in the result. 
Result so far: 7619.78
Deduct 720 from 800 and we're left with 80.
Since there are no more digits in the dividend, we add a zero to the remainder making it 800, and continue the process.

Moving on to step 9:
800 divided by 90 is 8 with a remainder of 80.
The number 8 becomes the next digit in our result. 
Result so far: 7619.788
Deduct 720 from 800 and we're left with 80.
Since there are no more digits in the dividend, we add a zero to the remainder making it 800, and continue the process.

The quotient of the division is 7619.788, and the remainder is 0.008.