We're dividing 8125030 by 409 
The aim is to understand the frequency of 409 in 8125030.

Advancing to step 1:
8 divided by 409 is 0 with a remainder of 8.
Use 0 as the next digit of our solution. 
Result so far: 0.0
The remainder is 8 after subtracting 0 from 8.
Append the next digit (1) from the dividend to 8 and continue with: 81 / 409

Let's proceed to step 2:
409 goes into 81 0 times with a remainder of 81.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 81, we end up with 81.
Take the next digit (2) from the dividend and append it to 81, then repeat: 812 / 409

Advancing to step 3:
409 can be fit into 812 1 times, resulting in a remainder of 403.
Put 1 as the next digit of the answer. 
Result so far: 1.0
The remainder is 403 after subtracting 409 from 812.
Take the next digit (5) from the dividend and append it to 403, then repeat: 4035 / 409

Going ahead to step 4:
409 can be fit into 4035 9 times, resulting in a remainder of 354.
Put 9 as the next digit of the answer. 
Result so far: 19.0
Subtract 3681 from 4035 to get 354.
Bring next digit (0) of the dividend behind the 354 and repeat the process: 3540 / 409

On to step 5:
3540 divided by 409 is 8 with a remainder of 268.
The number 8 becomes the next digit in our result. 
Result so far: 198.0
If we take 3272 away from 3540, we end up with 268.
Include the next digit (3) from the dividend after 268, then repeat: 2683 / 409

Let's proceed to step 6:
When dividing 2683 by 409, we get 6 with a remainder of 229.
Put 6 as the next digit of the answer. 
Result so far: 1986.0
The remainder is 229 after subtracting 2454 from 2683.
Include the next digit (0) from the dividend after 229, then repeat: 2290 / 409

On to step 7:
2290 divided by 409 is 5 with a remainder of 245.
Write down 5 as next digit of the result. 
Result so far: 19865.0
The remainder is 245 after subtracting 2045 from 2290.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2450, and continue the process.

Let's proceed to step 8:
409 goes into 2450 5 times with a remainder of 405.
The number 5 becomes the next digit in our result. 
Result so far: 19865.5
The remainder is 405 after subtracting 2045 from 2450.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4050, and continue the process.

On to step 9:
When dividing 4050 by 409, we get 9 with a remainder of 369.
Record the quotient 9 as the next digit in the result. 
Result so far: 19865.59
Subtracting 3681 from 4050 leaves us with 369.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3690, and continue the process.

On to step 10:
409 goes into 3690 9 times with a remainder of 9.
The number 9 becomes the next digit in our result. 
Result so far: 19865.599
If we subtract 3681 from 3690, we get 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

The final result is 19865.599 with a remainder of 0.0009.