61388 ÷ 15 
The aim is to understand the frequency of 15 in 61388.

Step 1:
6 divided by 15 is 0 with a remainder of 6.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtracting 0 from 6 leaves us with 6.
Grab the next digit (1) from the dividend, add it to 6, then carry on: 61 / 15

Step 2:
61 divided by 15 is 4 with a remainder of 1.
Write down 4 as next digit of the result. 
Result so far: 4.0
Subtract 60 from 61 to get 1.
Grab the next digit (3) from the dividend, add it to 1, then carry on: 13 / 15

Let's proceed to step 3:
The number 15 fits into 13 0 times, leaving a remainder of 13.
Write down 0 as next digit of the result. 
Result so far: 40.0
Subtract 0 from 13 to get 13.
Bring next digit (8) of the dividend behind the 13 and repeat the process: 138 / 15

Step 4:
The number 15 fits into 138 9 times, leaving a remainder of 3.
Use 9 as the next digit of our solution. 
Result so far: 409.0
Subtracting 135 from 138 leaves us with 3.
Fetch the next digit (8) from the dividend, attach it to 3 and continue: 38 / 15

Step 5:
If we divide 38 by 15, we get 2 and a remainder of 8.
The number 2 becomes the next digit in our result. 
Result so far: 4092.0
If we subtract 30 from 38, we get 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Going ahead to step 6:
The number 15 fits into 80 5 times, leaving a remainder of 5.
Use 5 as the next digit of our solution. 
Result so far: 4092.5
Subtract 75 from 80 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.

Let's proceed to step 7:
When dividing 50 by 15, we get 3 with a remainder of 5.
Use 3 as the next digit of our solution. 
Result so far: 4092.53
Subtract 45 from 50 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.

Moving on to step 8:
15 goes into 50 3 times with a remainder of 5.
Write down 3 as next digit of the result. 
Result so far: 4092.533
Deduct 45 from 50 and we're left 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.

After the division, we end up with 4092.533 and a remainder of 0.0005.