We divide 251581 by 99
The aim is to understand the frequency of 99 in 251581.

On to step 1:
When dividing 2 by 99, we get 0 with a remainder of 2.
The next digit of our result is 0. 
Result so far: 0.0
The remainder is 2 after subtracting 0 from 2.
Bring next digit (5) of the dividend behind the 2 and repeat the process: 25 / 99

Going ahead to step 2:
99 can be fit into 25 0 times, resulting in a remainder of 25.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we subtract 0 from 25, we get 25.
Bring next digit (1) of the dividend behind the 25 and repeat the process: 251 / 99

Advancing to step 3:
251 divided by 99 is 2 with a remainder of 53.
The number 2 becomes the next digit in our result. 
Result so far: 2.0
If we take 198 away from 251, we end up with 53.
Grab the next digit (5) from the dividend, add it to 53, then carry on: 535 / 99

Advancing to step 4:
535 divided by 99 is 5 with a remainder of 40.
Use 5 as the next digit of our solution. 
Result so far: 25.0
If we subtract 495 from 535, we get 40.
Include the next digit (8) from the dividend after 40, then repeat: 408 / 99

Going ahead to step 5:
The number 99 fits into 408 4 times, leaving a remainder of 12.
Record the quotient 4 as the next digit in the result. 
Result so far: 254.0
Subtract 396 from 408 to get 12.
Append the next digit (1) from the dividend to 12 and continue with: 121 / 99

Going ahead to step 6:
99 goes into 121 1 times with a remainder of 22.
Put 1 as the next digit of the answer. 
Result so far: 2541.0
Subtract 99 from 121 to get 22.
Since there are no more digits in the dividend, we add a zero to the remainder making it 220, and continue the process.

On to step 7:
If we divide 220 by 99, we get 2 and a remainder of 22.
The number 2 becomes the next digit in our result. 
Result so far: 2541.2
If we take 198 away from 220, we end up with 22.
Since there are no more digits in the dividend, we add a zero to the remainder making it 220, and continue the process.

On to step 8:
If we divide 220 by 99, we get 2 and a remainder of 22.
Record the quotient 2 as the next digit in the result. 
Result so far: 2541.22
Subtracting 198 from 220 leaves us with 22.
Since there are no more digits in the dividend, we add a zero to the remainder making it 220, and continue the process.

After the division, we end up with 2541.22 and a remainder of 0.022.