Let's divide 434578 by 90
The aim is to understand the frequency of 90 in 434578.

On to step 1:
90 can be fit into 4 0 times, resulting in a remainder of 4.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we take 0 away from 4, we end up with 4.
Take the next digit (3) from the dividend and append it to 4, then repeat: 43 / 90

Moving on to step 2:
90 can be fit into 43 0 times, resulting in a remainder of 43.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtracting 0 from 43 leaves us with 43.
Take the next digit (4) from the dividend and append it to 43, then repeat: 434 / 90

Advancing to step 3:
90 goes into 434 4 times with a remainder of 74.
Put 4 as the next digit of the answer. 
Result so far: 4.0
Subtracting 360 from 434 leaves us with 74.
Append the next digit (5) from the dividend to 74 and continue with: 745 / 90

On to step 4:
90 can be fit into 745 8 times, resulting in a remainder of 25.
Write down 8 as next digit of the result. 
Result so far: 48.0
The remainder is 25 after subtracting 720 from 745.
Bring next digit (7) of the dividend behind the 25 and repeat the process: 257 / 90

Going ahead to step 5:
90 can be fit into 257 2 times, resulting in a remainder of 77.
Use 2 as the next digit of our solution. 
Result so far: 482.0
If we subtract 180 from 257, we get 77.
Grab the next digit (8) from the dividend, add it to 77, then carry on: 778 / 90

On to step 6:
When dividing 778 by 90, we get 8 with a remainder of 58.
The number 8 becomes the next digit in our result. 
Result so far: 4828.0
Subtracting 720 from 778 leaves us with 58.
Since there are no more digits in the dividend, we add a zero to the remainder making it 580, and continue the process.

Let's proceed to step 7:
The number 90 fits into 580 6 times, leaving a remainder of 40.
Write down 6 as next digit of the result. 
Result so far: 4828.6
Subtract 540 from 580 to get 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

Let's proceed to step 8:
If we divide 400 by 90, we get 4 and a remainder of 40.
The number 4 becomes the next digit in our result. 
Result so far: 4828.64
Subtracting 360 from 400 leaves us with 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

Advancing to step 9:
The number 90 fits into 400 4 times, leaving a remainder of 40.
Record the quotient 4 as the next digit in the result. 
Result so far: 4828.644
If we take 360 away from 400, we end up with 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

The quotient of the division is 4828.644, and the remainder is 0.004.