We look at the division of 979731 by 15 
The aim is to understand the frequency of 15 in 979731.

Let's proceed to step 1:
The number 15 fits into 9 0 times, leaving a remainder of 9.
The next digit of our result is 0. 
Result so far: 0.0
Subtract 0 from 9 to get 9.
Bring next digit (7) of the dividend behind the 9 and repeat the process: 97 / 15

On to step 2:
97 divided by 15 is 6 with a remainder of 7.
Put 6 as the next digit of the answer. 
Result so far: 6.0
Subtracting 90 from 97 leaves us with 7.
Bring next digit (9) of the dividend behind the 7 and repeat the process: 79 / 15

Going ahead to step 3:
15 goes into 79 5 times with a remainder of 4.
Record the quotient 5 as the next digit in the result. 
Result so far: 65.0
If we take 75 away from 79, we end up with 4.
Include the next digit (7) from the dividend after 4, then repeat: 47 / 15

Moving on to step 4:
15 can be fit into 47 3 times, resulting in a remainder of 2.
Use 3 as the next digit of our solution. 
Result so far: 653.0
Subtracting 45 from 47 leaves us with 2.
Include the next digit (3) from the dividend after 2, then repeat: 23 / 15

Step 5:
15 goes into 23 1 times with a remainder of 8.
Put 1 as the next digit of the answer. 
Result so far: 6531.0
Subtracting 15 from 23 leaves us with 8.
Take the next digit (1) from the dividend and append it to 8, then repeat: 81 / 15

Step 6:
If we divide 81 by 15, we get 5 and a remainder of 6.
The number 5 becomes the next digit in our result. 
Result so far: 65315.0
Deduct 75 from 81 and we're left with 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

Step 7:
If we divide 60 by 15, we get 4 and a remainder of 0.
The number 4 becomes the next digit in our result. 
Result so far: 65315.4
Subtracting 60 from 60 leaves us 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.

Going ahead to step 8:
The number 15 fits into 0 0 times, leaving a remainder of 0.
Write down 0 as next digit of the result. 
Result so far: 65315.4
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.

Step 9:
If we divide 0 by 15, we get 0 and a remainder of 0.
The number 0 becomes the next digit in our result. 
Result so far: 65315.4
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.

The final result is 65315.4 with a remainder of 0.0.