Let's divide 261937 by 15
The aim is to understand the frequency of 15 in 261937.

Advancing to step 1:
When dividing 2 by 15, we get 0 with a remainder of 2.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtract 0 from 2 to get 2.
Grab the next digit (6) from the dividend, add it to 2, then carry on: 26 / 15

Advancing to step 2:
The number 15 fits into 26 1 times, leaving a remainder of 11.
Write down 1 as next digit of the result. 
Result so far: 1.0
Deduct 15 from 26 and we're left with 11.
Take the next digit (1) from the dividend and append it to 11, then repeat: 111 / 15

On to step 3:
111 divided by 15 is 7 with a remainder of 6.
Use 7 as the next digit of our solution. 
Result so far: 17.0
If we take 105 away from 111, we end up with 6.
Bring next digit (9) of the dividend behind the 6 and repeat the process: 69 / 15

Moving on to step 4:
If we divide 69 by 15, we get 4 and a remainder of 9.
The number 4 becomes the next digit in our result. 
Result so far: 174.0
Deduct 60 from 69 and we're left with 9.
Bring next digit (3) of the dividend behind the 9 and repeat the process: 93 / 15

On to step 5:
The number 15 fits into 93 6 times, leaving a remainder of 3.
The number 6 becomes the next digit in our result. 
Result so far: 1746.0
Deduct 90 from 93 and we're left with 3.
Fetch the next digit (7) from the dividend, attach it to 3 and continue: 37 / 15

Moving on to step 6:
The number 15 fits into 37 2 times, leaving a remainder of 7.
Write down 2 as next digit of the result. 
Result so far: 17462.0
If we take 30 away from 37, we end up with 7.
Since there are no more digits in the dividend, we add a zero to the remainder making it 70, and continue the process.

Advancing to step 7:
When dividing 70 by 15, we get 4 with a remainder of 10.
Put 4 as the next digit of the answer. 
Result so far: 17462.4
If we subtract 60 from 70, we get 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Step 8:
If we divide 100 by 15, we get 6 and a remainder of 10.
Use 6 as the next digit of our solution. 
Result so far: 17462.46
If we take 90 away from 100, 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 9:
If we divide 100 by 15, we get 6 and a remainder of 10.
Put 6 as the next digit of the answer. 
Result so far: 17462.466
Subtracting 90 from 100 leaves us 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.

After the division, we end up with 17462.466 and a remainder of 0.001.