We look at the division of 808366 by 15 
The aim is to understand the frequency of 15 in 808366.

Advancing to step 1:
15 can be fit into 8 0 times, resulting in a remainder of 8.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 8 to get 8.
Bring next digit (0) of the dividend behind the 8 and repeat the process: 80 / 15

Going ahead to step 2:
When dividing 80 by 15, we get 5 with a remainder of 5.
Record the quotient 5 as the next digit in the result. 
Result so far: 5.0
Subtracting 75 from 80 leaves us with 5.
Take the next digit (8) from the dividend and append it to 5, then repeat: 58 / 15

Step 3:
15 goes into 58 3 times with a remainder of 13.
Record the quotient 3 as the next digit in the result. 
Result so far: 53.0
If we take 45 away from 58, we end up with 13.
Bring next digit (3) of the dividend behind the 13 and repeat the process: 133 / 15

Moving on to step 4:
15 goes into 133 8 times with a remainder of 13.
Record the quotient 8 as the next digit in the result. 
Result so far: 538.0
Subtract 120 from 133 to get 13.
Include the next digit (6) from the dividend after 13, then repeat: 136 / 15

Advancing to step 5:
136 divided by 15 is 9 with a remainder of 1.
The next digit of our result is 9. 
Result so far: 5389.0
If we take 135 away from 136, we end up with 1.
Fetch the next digit (6) from the dividend, attach it to 1 and continue: 16 / 15

Going ahead to step 6:
If we divide 16 by 15, we get 1 and a remainder of 1.
Record the quotient 1 as the next digit in the result. 
Result so far: 53891.0
If we take 15 away from 16, we end up with 1.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

Moving on to step 7:
15 goes into 10 0 times with a remainder of 10.
The number 0 becomes the next digit in our result. 
Result so far: 53891.0
If we take 0 away from 10, we end up with 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Advancing to step 8:
The number 15 fits into 100 6 times, leaving a remainder of 10.
Record the quotient 6 as the next digit in the result. 
Result so far: 53891.06
Deduct 90 from 100 and we're left with 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Moving on to step 9:
When dividing 100 by 15, we get 6 with a remainder of 10.
Write down 6 as next digit of the result. 
Result so far: 53891.066
The remainder is 10 after subtracting 90 from 100.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

The final outcome is 53891.066, with a leftover of 0.001.