Let's divide 311537 by 15
The aim is to understand the frequency of 15 in 311537.

Let's proceed to step 1:
3 divided by 15 is 0 with a remainder of 3.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtracting 0 from 3 leaves us with 3.
Take the next digit (1) from the dividend and append it to 3, then repeat: 31 / 15

Let's proceed to step 2:
If we divide 31 by 15, we get 2 and a remainder of 1.
Record the quotient 2 as the next digit in the result. 
Result so far: 2.0
Subtracting 30 from 31 leaves us with 1.
Fetch the next digit (1) from the dividend, attach it to 1 and continue: 11 / 15

On to step 3:
15 goes into 11 0 times with a remainder of 11.
Put 0 as the next digit of the answer. 
Result so far: 20.0
The remainder is 11 after subtracting 0 from 11.
Append the next digit (5) from the dividend to 11 and continue with: 115 / 15

Going ahead to step 4:
15 can be fit into 115 7 times, resulting in a remainder of 10.
The number 7 becomes the next digit in our result. 
Result so far: 207.0
Subtract 105 from 115 to get 10.
Grab the next digit (3) from the dividend, add it to 10, then carry on: 103 / 15

Going ahead to step 5:
103 divided by 15 is 6 with a remainder of 13.
Write down 6 as next digit of the result. 
Result so far: 2076.0
Subtracting 90 from 103 leaves us with 13.
Include the next digit (7) from the dividend after 13, then repeat: 137 / 15

Advancing to step 6:
15 can be fit into 137 9 times, resulting in a remainder of 2.
Record the quotient 9 as the next digit in the result. 
Result so far: 20769.0
Subtract 135 from 137 to get 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

Step 7:
When dividing 20 by 15, we get 1 with a remainder of 5.
Put 1 as the next digit of the answer. 
Result so far: 20769.1
Subtract 15 from 20 to get 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Going ahead to step 8:
15 can be fit into 50 3 times, resulting in a remainder of 5.
Write down 3 as next digit of the result. 
Result so far: 20769.13
If we take 45 away from 50, we end up 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.

Step 9:
If we divide 50 by 15, we get 3 and a remainder of 5.
The number 3 becomes the next digit in our result. 
Result so far: 20769.133
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.

The final result is 20769.133 with a remainder of 0.0005.