We divide 866823 by 15
The aim is to understand the frequency of 15 in 866823.

Moving on 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
Deduct 0 from 8 and we're left with 8.
Fetch the next digit (6) from the dividend, attach it to 8 and continue: 86 / 15

Moving on to step 2:
If we divide 86 by 15, we get 5 and a remainder of 11.
Record the quotient 5 as the next digit in the result. 
Result so far: 5.0
Deduct 75 from 86 and we're left with 11.
Grab the next digit (6) from the dividend, add it to 11, then carry on: 116 / 15

Moving on to step 3:
15 goes into 116 7 times with a remainder of 11.
Use 7 as the next digit of our solution. 
Result so far: 57.0
Subtracting 105 from 116 leaves us with 11.
Append the next digit (8) from the dividend to 11 and continue with: 118 / 15

Moving on to step 4:
The number 15 fits into 118 7 times, leaving a remainder of 13.
The next digit of our result is 7. 
Result so far: 577.0
If we take 105 away from 118, we end up with 13.
Append the next digit (2) from the dividend to 13 and continue with: 132 / 15

Moving on to step 5:
15 goes into 132 8 times with a remainder of 12.
Put 8 as the next digit of the answer. 
Result so far: 5778.0
If we take 120 away from 132, we end up with 12.
Bring next digit (3) of the dividend behind the 12 and repeat the process: 123 / 15

Let's proceed to step 6:
If we divide 123 by 15, we get 8 and a remainder of 3.
The number 8 becomes the next digit in our result. 
Result so far: 57788.0
If we take 120 away from 123, we end up with 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

Moving on to step 7:
15 goes into 30 2 times with a remainder of 0.
Put 2 as the next digit of the answer. 
Result so far: 57788.2
If we take 30 away from 30, we end up 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.

On to step 8:
When dividing 0 by 15, we get 0 with a remainder of 0.
Use 0 as the next digit of our solution. 
Result so far: 57788.2
The remainder is 0 after subtracting 0 from 0.
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 9:
When dividing 0 by 15, we get 0 with a remainder of 0.
Record the quotient 0 as the next digit in the result. 
Result so far: 57788.2
Subtracting 0 from 0 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.

After the division, we end up with 57788.2 and a remainder of 0.0.