We divide 819664 by 90
The aim is to understand the frequency of 90 in 819664.

Let's proceed to step 1:
90 can be fit into 8 0 times, resulting in a remainder of 8.
The next digit of our result is 0. 
Result so far: 0.0
The remainder is 8 after subtracting 0 from 8.
Include the next digit (1) from the dividend after 8, then repeat: 81 / 90

Let's proceed to step 2:
90 goes into 81 0 times with a remainder of 81.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 81, we end up with 81.
Take the next digit (9) from the dividend and append it to 81, then repeat: 819 / 90

Let's proceed to step 3:
When dividing 819 by 90, we get 9 with a remainder of 9.
Write down 9 as next digit of the result. 
Result so far: 9.0
If we take 810 away from 819, we end up with 9.
Take the next digit (6) from the dividend and append it to 9, then repeat: 96 / 90

Let's proceed to step 4:
The number 90 fits into 96 1 times, leaving a remainder of 6.
Use 1 as the next digit of our solution. 
Result so far: 91.0
Subtract 90 from 96 to get 6.
Grab the next digit (6) from the dividend, add it to 6, then carry on: 66 / 90

Let's proceed to step 5:
If we divide 66 by 90, we get 0 and a remainder of 66.
Use 0 as the next digit of our solution. 
Result so far: 910.0
If we subtract 0 from 66, we get 66.
Append the next digit (4) from the dividend to 66 and continue with: 664 / 90

On to step 6:
90 can be fit into 664 7 times, resulting in a remainder of 34.
Put 7 as the next digit of the answer. 
Result so far: 9107.0
If we take 630 away from 664, we end up with 34.
Since there are no more digits in the dividend, we add a zero to the remainder making it 340, and continue the process.

Going ahead to step 7:
340 divided by 90 is 3 with a remainder of 70.
Put 3 as the next digit of the answer. 
Result so far: 9107.3
Deduct 270 from 340 and we're left with 70.
Since there are no more digits in the dividend, we add a zero to the remainder making it 700, and continue the process.

Moving on to step 8:
If we divide 700 by 90, we get 7 and a remainder of 70.
Use 7 as the next digit of our solution. 
Result so far: 9107.37
The remainder is 70 after subtracting 630 from 700.
Since there are no more digits in the dividend, we add a zero to the remainder making it 700, and continue the process.

Going ahead to step 9:
90 goes into 700 7 times with a remainder of 70.
The next digit of our result is 7. 
Result so far: 9107.377
Subtracting 630 from 700 leaves us with 70.
Since there are no more digits in the dividend, we add a zero to the remainder making it 700, and continue the process.

Our division results in 9107.377 with a remaining 0.007.