129252 ÷ 15 
The aim is to understand the frequency of 15 in 129252.

Going ahead to step 1:
If we divide 1 by 15, we get 0 and a remainder of 1.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtracting 0 from 1 leaves us with 1.
Take the next digit (2) from the dividend and append it to 1, then repeat: 12 / 15

Step 2:
15 goes into 12 0 times with a remainder of 12.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 12 to get 12.
Include the next digit (9) from the dividend after 12, then repeat: 129 / 15

Let's proceed to step 3:
15 goes into 129 8 times with a remainder of 9.
The next digit of our result is 8. 
Result so far: 8.0
Subtract 120 from 129 to get 9.
Append the next digit (2) from the dividend to 9 and continue with: 92 / 15

Moving on to step 4:
15 can be fit into 92 6 times, resulting in a remainder of 2.
Write down 6 as next digit of the result. 
Result so far: 86.0
If we subtract 90 from 92, we get 2.
Bring next digit (5) of the dividend behind the 2 and repeat the process: 25 / 15

Let's proceed to step 5:
The number 15 fits into 25 1 times, leaving a remainder of 10.
The next digit of our result is 1. 
Result so far: 861.0
Subtracting 15 from 25 leaves us with 10.
Fetch the next digit (2) from the dividend, attach it to 10 and continue: 102 / 15

On to step 6:
When dividing 102 by 15, we get 6 with a remainder of 12.
Put 6 as the next digit of the answer. 
Result so far: 8616.0
Subtract 90 from 102 to get 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

On to step 7:
If we divide 120 by 15, we get 8 and a remainder of 0.
Use 8 as the next digit of our solution. 
Result so far: 8616.8
If we take 120 away from 120, we end up with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Let's proceed to step 8:
15 can be fit into 0 0 times, resulting in a remainder of 0.
Record the quotient 0 as the next digit in the result. 
Result so far: 8616.8
If we subtract 0 from 0, we get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Step 9:
When dividing 0 by 15, we get 0 with a remainder of 0.
Write down 0 as next digit of the result. 
Result so far: 8616.8
Deduct 0 from 0 and we're left with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Our division results in 8616.8 with a remaining 0.0.