612308 ÷ 90 
The aim is to understand the frequency of 90 in 612308.

Going ahead to step 1:
When dividing 6 by 90, we get 0 with a remainder of 6.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 6, we end up with 6.
Append the next digit (1) from the dividend to 6 and continue with: 61 / 90

Moving on to step 2:
61 divided by 90 is 0 with a remainder of 61.
The next digit of our result is 0. 
Result so far: 0.0
Subtracting 0 from 61 leaves us with 61.
Fetch the next digit (2) from the dividend, attach it to 61 and continue: 612 / 90

Advancing to step 3:
90 goes into 612 6 times with a remainder of 72.
The next digit of our result is 6. 
Result so far: 6.0
If we take 540 away from 612, we end up with 72.
Bring next digit (3) of the dividend behind the 72 and repeat the process: 723 / 90

Advancing to step 4:
723 divided by 90 is 8 with a remainder of 3.
The number 8 becomes the next digit in our result. 
Result so far: 68.0
Subtract 720 from 723 to get 3.
Take the next digit (0) from the dividend and append it to 3, then repeat: 30 / 90

On to step 5:
When dividing 30 by 90, we get 0 with a remainder of 30.
Use 0 as the next digit of our solution. 
Result so far: 680.0
If we subtract 0 from 30, we get 30.
Append the next digit (8) from the dividend to 30 and continue with: 308 / 90

Let's proceed to step 6:
When dividing 308 by 90, we get 3 with a remainder of 38.
The number 3 becomes the next digit in our result. 
Result so far: 6803.0
If we subtract 270 from 308, we get 38.
Since there are no more digits in the dividend, we add a zero to the remainder making it 380, and continue the process.

Going ahead to step 7:
When dividing 380 by 90, we get 4 with a remainder of 20.
Record the quotient 4 as the next digit in the result. 
Result so far: 6803.4
The remainder is 20 after subtracting 360 from 380.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Let's proceed to step 8:
90 goes into 200 2 times with a remainder of 20.
Put 2 as the next digit of the answer. 
Result so far: 6803.42
If we take 180 away from 200, 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.

Moving on to step 9:
When dividing 200 by 90, we get 2 with a remainder of 20.
Use 2 as the next digit of our solution. 
Result so far: 6803.422
The remainder is 20 after subtracting 180 from 200.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

The final result is 6803.422 with a remainder of 0.002.