We look at the division of 865071 by 15 
The aim is to understand the frequency of 15 in 865071.

Advancing to step 1:
15 goes into 8 0 times with a remainder of 8.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtracting 0 from 8 leaves us with 8.
Grab the next digit (6) from the dividend, add it to 8, then carry on: 86 / 15

Advancing to step 2:
If we divide 86 by 15, we get 5 and a remainder of 11.
The next digit of our result is 5. 
Result so far: 5.0
If we subtract 75 from 86, we get 11.
Include the next digit (5) from the dividend after 11, then repeat: 115 / 15

Let's proceed to step 3:
115 divided by 15 is 7 with a remainder of 10.
The number 7 becomes the next digit in our result. 
Result so far: 57.0
Subtract 105 from 115 to get 10.
Append the next digit (0) from the dividend to 10 and continue with: 100 / 15

Moving on to step 4:
15 goes into 100 6 times with a remainder of 10.
The number 6 becomes the next digit in our result. 
Result so far: 576.0
If we take 90 away from 100, we end up with 10.
Include the next digit (7) from the dividend after 10, then repeat: 107 / 15

Going ahead to step 5:
When dividing 107 by 15, we get 7 with a remainder of 2.
Record the quotient 7 as the next digit in the result. 
Result so far: 5767.0
The remainder is 2 after subtracting 105 from 107.
Bring next digit (1) of the dividend behind the 2 and repeat the process: 21 / 15

Step 6:
The number 15 fits into 21 1 times, leaving a remainder of 6.
Use 1 as the next digit of our solution. 
Result so far: 57671.0
Subtracting 15 from 21 leaves us 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.

On to step 7:
15 can be fit into 60 4 times, resulting in a remainder of 0.
Use 4 as the next digit of our solution. 
Result so far: 57671.4
Deduct 60 from 60 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.

Advancing to step 8:
15 can be fit into 0 0 times, resulting in a remainder of 0.
The number 0 becomes the next digit in our result. 
Result so far: 57671.4
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.

Advancing to step 9:
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: 57671.4
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.

The quotient of the division is 57671.4, and the remainder is 0.0.