We look at the division of 505531 by 99 
The aim is to understand the frequency of 99 in 505531.

Going ahead to step 1:
The number 99 fits into 5 0 times, leaving a remainder of 5.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we subtract 0 from 5, we get 5.
Append the next digit (0) from the dividend to 5 and continue with: 50 / 99

Let's proceed to step 2:
99 can be fit into 50 0 times, resulting in a remainder of 50.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtract 0 from 50 to get 50.
Include the next digit (5) from the dividend after 50, then repeat: 505 / 99

Going ahead to step 3:
If we divide 505 by 99, we get 5 and a remainder of 10.
The number 5 becomes the next digit in our result. 
Result so far: 5.0
The remainder is 10 after subtracting 495 from 505.
Append the next digit (5) from the dividend to 10 and continue with: 105 / 99

Let's proceed to step 4:
99 can be fit into 105 1 times, resulting in a remainder of 6.
The next digit of our result is 1. 
Result so far: 51.0
Subtracting 99 from 105 leaves us with 6.
Fetch the next digit (3) from the dividend, attach it to 6 and continue: 63 / 99

Advancing to step 5:
63 divided by 99 is 0 with a remainder of 63.
Record the quotient 0 as the next digit in the result. 
Result so far: 510.0
Deduct 0 from 63 and we're left with 63.
Append the next digit (1) from the dividend to 63 and continue with: 631 / 99

Advancing to step 6:
If we divide 631 by 99, we get 6 and a remainder of 37.
Use 6 as the next digit of our solution. 
Result so far: 5106.0
Deduct 594 from 631 and we're left with 37.
Since there are no more digits in the dividend, we add a zero to the remainder making it 370, and continue the process.

Let's proceed to step 7:
The number 99 fits into 370 3 times, leaving a remainder of 73.
Write down 3 as next digit of the result. 
Result so far: 5106.3
Subtract 297 from 370 to get 73.
Since there are no more digits in the dividend, we add a zero to the remainder making it 730, and continue the process.

Going ahead to step 8:
730 divided by 99 is 7 with a remainder of 37.
Use 7 as the next digit of our solution. 
Result so far: 5106.37
Subtract 693 from 730 to get 37.
Since there are no more digits in the dividend, we add a zero to the remainder making it 370, and continue the process.

Advancing to step 9:
370 divided by 99 is 3 with a remainder of 73.
Put 3 as the next digit of the answer. 
Result so far: 5106.373
If we take 297 away from 370, we end up with 73.
Since there are no more digits in the dividend, we add a zero to the remainder making it 730, and continue the process.

Step 10:
If we divide 730 by 99, we get 7 and a remainder of 37.
Record the quotient 7 as the next digit in the result. 
Result so far: 5106.3737
The remainder is 37 after subtracting 693 from 730.
Since there are no more digits in the dividend, we add a zero to the remainder making it 370, and continue the process.

Moving on to step 11:
99 can be fit into 370 3 times, resulting in a remainder of 73.
Use 3 as the next digit of our solution. 
Result so far: 5106.37373
Deduct 297 from 370 and we're left with 73.
Since there are no more digits in the dividend, we add a zero to the remainder making it 730, and continue the process.

On to step 12:
If we divide 730 by 99, we get 7 and a remainder of 37.
Use 7 as the next digit of our solution. 
Result so far: 5106.373737
Deduct 693 from 730 and we're left with 37.
Since there are no more digits in the dividend, we add a zero to the remainder making it 370, and continue the process.

On to step 13:
The number 99 fits into 370 3 times, leaving a remainder of 73.
Use 3 as the next digit of our solution. 
Result so far: 5106.3737373
The remainder is 73 after subtracting 297 from 370.
Since there are no more digits in the dividend, we add a zero to the remainder making it 730, and continue the process.

Step 14:
99 goes into 730 7 times with a remainder of 37.
The number 7 becomes the next digit in our result. 
Result so far: 5106.37373737
The remainder is 37 after subtracting 693 from 730.
Since there are no more digits in the dividend, we add a zero to the remainder making it 370, and continue the process.

The final outcome is 5106.37373737, with a leftover of 3.7e-08.