We look at the division of 250690 by 15 
The aim is to understand the frequency of 15 in 250690.

Going ahead to step 1:
When dividing 2 by 15, we get 0 with a remainder of 2.
The next digit of our result is 0. 
Result so far: 0.0
Subtract 0 from 2 to get 2.
Take the next digit (5) from the dividend and append it to 2, then repeat: 25 / 15

Step 2:
15 can be fit into 25 1 times, resulting in a remainder of 10.
Write down 1 as next digit of the result. 
Result so far: 1.0
Subtract 15 from 25 to get 10.
Bring next digit (0) of the dividend behind the 10 and repeat the process: 100 / 15

Moving on to step 3:
When dividing 100 by 15, we get 6 with a remainder of 10.
Use 6 as the next digit of our solution. 
Result so far: 16.0
Subtracting 90 from 100 leaves us with 10.
Take the next digit (6) from the dividend and append it to 10, then repeat: 106 / 15

Let's proceed to step 4:
If we divide 106 by 15, we get 7 and a remainder of 1.
Record the quotient 7 as the next digit in the result. 
Result so far: 167.0
Deduct 105 from 106 and we're left with 1.
Take the next digit (9) from the dividend and append it to 1, then repeat: 19 / 15

Let's proceed to step 5:
15 can be fit into 19 1 times, resulting in a remainder of 4.
Record the quotient 1 as the next digit in the result. 
Result so far: 1671.0
The remainder is 4 after subtracting 15 from 19.
Bring next digit (0) of the dividend behind the 4 and repeat the process: 40 / 15

Moving on to step 6:
When dividing 40 by 15, we get 2 with a remainder of 10.
The next digit of our result is 2. 
Result so far: 16712.0
Subtract 30 from 40 to 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.

On to step 7:
15 can be fit into 100 6 times, resulting in a remainder of 10.
Put 6 as the next digit of the answer. 
Result so far: 16712.6
Subtract 90 from 100 to 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.

Moving on to step 8:
When dividing 100 by 15, we get 6 with a remainder of 10.
Put 6 as the next digit of the answer. 
Result so far: 16712.66
The remainder is 10 after subtracting 90 from 100.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

The final outcome is 16712.66, with a leftover of 0.01.