We look at the division of 251283 by 15 
The aim is to understand the frequency of 15 in 251283.

Advancing to step 1:
2 divided by 15 is 0 with a remainder of 2.
The next digit of our result is 0. 
Result so far: 0.0
Subtract 0 from 2 to get 2.
Append the next digit (5) from the dividend to 2 and continue with: 25 / 15

Going ahead to step 2:
If we divide 25 by 15, we get 1 and a remainder of 10.
The number 1 becomes the next digit in our result. 
Result so far: 1.0
If we take 15 away from 25, we end up with 10.
Take the next digit (1) from the dividend and append it to 10, then repeat: 101 / 15

Advancing to step 3:
If we divide 101 by 15, we get 6 and a remainder of 11.
The next digit of our result is 6. 
Result so far: 16.0
Subtract 90 from 101 to get 11.
Fetch the next digit (2) from the dividend, attach it to 11 and continue: 112 / 15

Going ahead to step 4:
112 divided by 15 is 7 with a remainder of 7.
The number 7 becomes the next digit in our result. 
Result so far: 167.0
The remainder is 7 after subtracting 105 from 112.
Include the next digit (8) from the dividend after 7, then repeat: 78 / 15

Advancing to step 5:
15 can be fit into 78 5 times, resulting in a remainder of 3.
Write down 5 as next digit of the result. 
Result so far: 1675.0
If we subtract 75 from 78, we get 3.
Fetch the next digit (3) from the dividend, attach it to 3 and continue: 33 / 15

On to step 6:
When dividing 33 by 15, we get 2 with a remainder of 3.
Write down 2 as next digit of the result. 
Result so far: 16752.0
Subtract 30 from 33 to get 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

Step 7:
15 can be fit into 30 2 times, resulting in a remainder of 0.
Put 2 as the next digit of the answer. 
Result so far: 16752.2
The remainder is 0 after subtracting 30 from 30.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Moving on to step 8:
When dividing 0 by 15, we get 0 with a remainder of 0.
The number 0 becomes the next digit in our result. 
Result so far: 16752.2
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:
If we divide 0 by 15, we get 0 and a remainder of 0.
Record the quotient 0 as the next digit in the result. 
Result so far: 16752.2
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.

Our division results in 16752.2 with a remaining 0.0.