215909 divided by 9 
The aim is to understand the frequency of 9 in 215909.

Let's proceed to step 1:
When dividing 2 by 9, we get 0 with a remainder of 2.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Deduct 0 from 2 and we're left with 2.
Bring next digit (1) of the dividend behind the 2 and repeat the process: 21 / 9

Let's proceed to step 2:
When dividing 21 by 9, we get 2 with a remainder of 3.
The number 2 becomes the next digit in our result. 
Result so far: 2.0
Deduct 18 from 21 and we're left with 3.
Append the next digit (5) from the dividend to 3 and continue with: 35 / 9

Going ahead to step 3:
9 can be fit into 35 3 times, resulting in a remainder of 8.
Put 3 as the next digit of the answer. 
Result so far: 23.0
The remainder is 8 after subtracting 27 from 35.
Append the next digit (9) from the dividend to 8 and continue with: 89 / 9

Advancing to step 4:
The number 9 fits into 89 9 times, leaving a remainder of 8.
Use 9 as the next digit of our solution. 
Result so far: 239.0
The remainder is 8 after subtracting 81 from 89.
Include the next digit (0) from the dividend after 8, then repeat: 80 / 9

Going ahead to step 5:
80 divided by 9 is 8 with a remainder of 8.
Use 8 as the next digit of our solution. 
Result so far: 2398.0
If we take 72 away from 80, we end up with 8.
Append the next digit (9) from the dividend to 8 and continue with: 89 / 9

On to step 6:
9 can be fit into 89 9 times, resulting in a remainder of 8.
Put 9 as the next digit of the answer. 
Result so far: 23989.0
Deduct 81 from 89 and we're left 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.

Moving on to step 7:
When dividing 80 by 9, we get 8 with a remainder of 8.
Record the quotient 8 as the next digit in the result. 
Result so far: 23989.8
The remainder is 8 after subtracting 72 from 80.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Moving on to step 8:
If we divide 80 by 9, we get 8 and a remainder of 8.
Put 8 as the next digit of the answer. 
Result so far: 23989.88
Deduct 72 from 80 and we're left 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.

Our division results in 23989.88 with a remaining 0.008.