Let's divide 870113 by 15
The aim is to understand the frequency of 15 in 870113.

On to step 1:
15 can be fit into 8 0 times, resulting in a remainder of 8.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtracting 0 from 8 leaves us with 8.
Append the next digit (7) from the dividend to 8 and continue with: 87 / 15

Going ahead to step 2:
15 goes into 87 5 times with a remainder of 12.
The next digit of our result is 5. 
Result so far: 5.0
Subtract 75 from 87 to get 12.
Bring next digit (0) of the dividend behind the 12 and repeat the process: 120 / 15

Let's proceed to step 3:
15 goes into 120 8 times with a remainder of 0.
Record the quotient 8 as the next digit in the result. 
Result so far: 58.0
Subtracting 120 from 120 leaves us with 0.
Take the next digit (1) from the dividend and append it to 0, then repeat: 1 / 15

Advancing to step 4:
1 divided by 15 is 0 with a remainder of 1.
Put 0 as the next digit of the answer. 
Result so far: 580.0
Subtracting 0 from 1 leaves us with 1.
Append the next digit (1) from the dividend to 1 and continue with: 11 / 15

Going ahead to step 5:
15 goes into 11 0 times with a remainder of 11.
The number 0 becomes the next digit in our result. 
Result so far: 5800.0
If we subtract 0 from 11, we get 11.
Append the next digit (3) from the dividend to 11 and continue with: 113 / 15

Going ahead to step 6:
When dividing 113 by 15, we get 7 with a remainder of 8.
Record the quotient 7 as the next digit in the result. 
Result so far: 58007.0
Subtracting 105 from 113 leaves us with 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 7:
The number 15 fits into 80 5 times, leaving a remainder of 5.
The next digit of our result is 5. 
Result so far: 58007.5
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.

Going ahead to step 8:
15 goes into 50 3 times with a remainder of 5.
Use 3 as the next digit of our solution. 
Result so far: 58007.53
The remainder is 5 after subtracting 45 from 50.
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 9:
When dividing 50 by 15, we get 3 with a remainder of 5.
Record the quotient 3 as the next digit in the result. 
Result so far: 58007.533
The remainder is 5 after subtracting 45 from 50.
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 58007.533 with a remainder of 0.0005.