860343 divided by 15 
The aim is to understand the frequency of 15 in 860343.

Let's proceed to step 1:
The number 15 fits into 8 0 times, leaving a remainder of 8.
The next digit of our result is 0. 
Result so far: 0.0
If we subtract 0 from 8, we get 8.
Bring next digit (6) of the dividend behind the 8 and repeat the process: 86 / 15

Moving on to step 2:
15 goes into 86 5 times with a remainder of 11.
Write down 5 as next digit of the result. 
Result so far: 5.0
The remainder is 11 after subtracting 75 from 86.
Grab the next digit (0) from the dividend, add it to 11, then carry on: 110 / 15

Step 3:
When dividing 110 by 15, we get 7 with a remainder of 5.
Put 7 as the next digit of the answer. 
Result so far: 57.0
Deduct 105 from 110 and we're left with 5.
Fetch the next digit (3) from the dividend, attach it to 5 and continue: 53 / 15

Let's proceed to step 4:
15 can be fit into 53 3 times, resulting in a remainder of 8.
Record the quotient 3 as the next digit in the result. 
Result so far: 573.0
Subtracting 45 from 53 leaves us with 8.
Grab the next digit (4) from the dividend, add it to 8, then carry on: 84 / 15

Advancing to step 5:
15 can be fit into 84 5 times, resulting in a remainder of 9.
Write down 5 as next digit of the result. 
Result so far: 5735.0
Subtract 75 from 84 to get 9.
Grab the next digit (3) from the dividend, add it to 9, then carry on: 93 / 15

Advancing to step 6:
The number 15 fits into 93 6 times, leaving a remainder of 3.
Use 6 as the next digit of our solution. 
Result so far: 57356.0
Deduct 90 from 93 and we're left 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.

Advancing to step 7:
The number 15 fits into 30 2 times, leaving a remainder of 0.
The next digit of our result is 2. 
Result so far: 57356.2
Deduct 30 from 30 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 8:
15 goes into 0 0 times with a remainder of 0.
Record the quotient 0 as the next digit in the result. 
Result so far: 57356.2
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.

Going ahead to step 9:
When dividing 0 by 15, we get 0 with a remainder of 0.
The next digit of our result is 0. 
Result so far: 57356.2
If we take 0 away from 0, 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.

The final result is 57356.2 with a remainder of 0.0.