We look at the division of 856355 by 15 
The aim is to understand the frequency of 15 in 856355.

Advancing to step 1:
15 can be fit into 8 0 times, resulting in a remainder of 8.
The next digit of our result is 0. 
Result so far: 0.0
If we subtract 0 from 8, we get 8.
Bring next digit (5) of the dividend behind the 8 and repeat the process: 85 / 15

Let's proceed to step 2:
The number 15 fits into 85 5 times, leaving a remainder of 10.
Put 5 as the next digit of the answer. 
Result so far: 5.0
Deduct 75 from 85 and we're left with 10.
Include the next digit (6) from the dividend after 10, then repeat: 106 / 15

Let's proceed to step 3:
15 can be fit into 106 7 times, resulting in a remainder of 1.
The number 7 becomes the next digit in our result. 
Result so far: 57.0
The remainder is 1 after subtracting 105 from 106.
Fetch the next digit (3) from the dividend, attach it to 1 and continue: 13 / 15

On to step 4:
13 divided by 15 is 0 with a remainder of 13.
The next digit of our result is 0. 
Result so far: 570.0
If we take 0 away from 13, we end up with 13.
Bring next digit (5) of the dividend behind the 13 and repeat the process: 135 / 15

Moving on to step 5:
15 can be fit into 135 9 times, resulting in a remainder of 0.
The number 9 becomes the next digit in our result. 
Result so far: 5709.0
If we subtract 135 from 135, we get 0.
Include the next digit (5) from the dividend after 0, then repeat: 5 / 15

On to step 6:
15 can be fit into 5 0 times, resulting in a remainder of 5.
The number 0 becomes the next digit in our result. 
Result so far: 57090.0
Subtracting 0 from 5 leaves us with 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Let's proceed to step 7:
If we divide 50 by 15, we get 3 and a remainder of 5.
Write down 3 as next digit of the result. 
Result so far: 57090.3
Subtracting 45 from 50 leaves us with 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Advancing to step 8:
The number 15 fits into 50 3 times, leaving a remainder of 5.
Use 3 as the next digit of our solution. 
Result so far: 57090.33
Deduct 45 from 50 and we're left with 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

The final result is 57090.33 with a remainder of 0.005.