145318 ÷ 90 
The aim is to understand the frequency of 90 in 145318.

Advancing to step 1:
When dividing 1 by 90, we get 0 with a remainder of 1.
The next digit of our result is 0. 
Result so far: 0.0
The remainder is 1 after subtracting 0 from 1.
Take the next digit (4) from the dividend and append it to 1, then repeat: 14 / 90

Advancing to step 2:
The number 90 fits into 14 0 times, leaving a remainder of 14.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 14, we end up with 14.
Take the next digit (5) from the dividend and append it to 14, then repeat: 145 / 90

On to step 3:
The number 90 fits into 145 1 times, leaving a remainder of 55.
Record the quotient 1 as the next digit in the result. 
Result so far: 1.0
Deduct 90 from 145 and we're left with 55.
Bring next digit (3) of the dividend behind the 55 and repeat the process: 553 / 90

Let's proceed to step 4:
553 divided by 90 is 6 with a remainder of 13.
The number 6 becomes the next digit in our result. 
Result so far: 16.0
If we take 540 away from 553, we end up with 13.
Grab the next digit (1) from the dividend, add it to 13, then carry on: 131 / 90

On to step 5:
90 goes into 131 1 times with a remainder of 41.
Record the quotient 1 as the next digit in the result. 
Result so far: 161.0
Subtract 90 from 131 to get 41.
Bring next digit (8) of the dividend behind the 41 and repeat the process: 418 / 90

On to step 6:
418 divided by 90 is 4 with a remainder of 58.
Write down 4 as next digit of the result. 
Result so far: 1614.0
If we take 360 away from 418, we end up 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:
90 goes into 580 6 times with a remainder of 40.
Record the quotient 6 as the next digit in the result. 
Result so far: 1614.6
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 next digit of our result is 4. 
Result so far: 1614.64
Subtract 360 from 400 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.

On to step 9:
90 goes into 400 4 times with a remainder of 40.
The number 4 becomes the next digit in our result. 
Result so far: 1614.644
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.

Our division results in 1614.644 with a remaining 0.004.