We're dividing 133986 by 15 
The aim is to understand the frequency of 15 in 133986.

On to step 1:
15 can be fit into 1 0 times, resulting in a remainder of 1.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtract 0 from 1 to get 1.
Append the next digit (3) from the dividend to 1 and continue with: 13 / 15

Going ahead to step 2:
13 divided by 15 is 0 with a remainder of 13.
Write down 0 as next digit of the result. 
Result so far: 0.0
Deduct 0 from 13 and we're left with 13.
Include the next digit (3) from the dividend after 13, then repeat: 133 / 15

Advancing to step 3:
The number 15 fits into 133 8 times, leaving a remainder of 13.
The next digit of our result is 8. 
Result so far: 8.0
The remainder is 13 after subtracting 120 from 133.
Take the next digit (9) from the dividend and append it to 13, then repeat: 139 / 15

Going ahead to step 4:
The number 15 fits into 139 9 times, leaving a remainder of 4.
Record the quotient 9 as the next digit in the result. 
Result so far: 89.0
If we subtract 135 from 139, we get 4.
Bring next digit (8) of the dividend behind the 4 and repeat the process: 48 / 15

Moving on to step 5:
If we divide 48 by 15, we get 3 and a remainder of 3.
The next digit of our result is 3. 
Result so far: 893.0
Subtracting 45 from 48 leaves us with 3.
Grab the next digit (6) from the dividend, add it to 3, then carry on: 36 / 15

Going ahead to step 6:
The number 15 fits into 36 2 times, leaving a remainder of 6.
Use 2 as the next digit of our solution. 
Result so far: 8932.0
If we take 30 away from 36, we end up 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.

Advancing to step 7:
When dividing 60 by 15, we get 4 with a remainder of 0.
Use 4 as the next digit of our solution. 
Result so far: 8932.4
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.

On to step 8:
0 divided by 15 is 0 with a remainder of 0.
Use 0 as the next digit of our solution. 
Result so far: 8932.4
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.

Advancing to step 9:
When dividing 0 by 15, we get 0 with a remainder of 0.
Write down 0 as next digit of the result. 
Result so far: 8932.4
Subtract 0 from 0 to 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.

After the division, we end up with 8932.4 and a remainder of 0.0.