17728921 divided by 355 
The aim is to understand the frequency of 355 in 17728921.

Advancing to step 1:
The number 355 fits into 1 0 times, leaving a remainder of 1.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtracting 0 from 1 leaves us with 1.
Include the next digit (7) from the dividend after 1, then repeat: 17 / 355

On to step 2:
355 goes into 17 0 times with a remainder of 17.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we take 0 away from 17, we end up with 17.
Bring next digit (7) of the dividend behind the 17 and repeat the process: 177 / 355

Going ahead to step 3:
355 goes into 177 0 times with a remainder of 177.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we subtract 0 from 177, we get 177.
Grab the next digit (2) from the dividend, add it to 177, then carry on: 1772 / 355

On to step 4:
1772 divided by 355 is 4 with a remainder of 352.
Put 4 as the next digit of the answer. 
Result so far: 4.0
If we take 1420 away from 1772, we end up with 352.
Take the next digit (8) from the dividend and append it to 352, then repeat: 3528 / 355

Let's proceed to step 5:
3528 divided by 355 is 9 with a remainder of 333.
Record the quotient 9 as the next digit in the result. 
Result so far: 49.0
Subtract 3195 from 3528 to get 333.
Fetch the next digit (9) from the dividend, attach it to 333 and continue: 3339 / 355

On to step 6:
355 can be fit into 3339 9 times, resulting in a remainder of 144.
Use 9 as the next digit of our solution. 
Result so far: 499.0
The remainder is 144 after subtracting 3195 from 3339.
Grab the next digit (2) from the dividend, add it to 144, then carry on: 1442 / 355

Moving on to step 7:
1442 divided by 355 is 4 with a remainder of 22.
Record the quotient 4 as the next digit in the result. 
Result so far: 4994.0
The remainder is 22 after subtracting 1420 from 1442.
Append the next digit (1) from the dividend to 22 and continue with: 221 / 355

Step 8:
221 divided by 355 is 0 with a remainder of 221.
Use 0 as the next digit of our solution. 
Result so far: 49940.0
The remainder is 221 after subtracting 0 from 221.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2210, and continue the process.

Going ahead to step 9:
355 goes into 2210 6 times with a remainder of 80.
Put 6 as the next digit of the answer. 
Result so far: 49940.6
If we take 2130 away from 2210, we end up with 80.
Since there are no more digits in the dividend, we add a zero to the remainder making it 800, and continue the process.

Step 10:
When dividing 800 by 355, we get 2 with a remainder of 90.
Put 2 as the next digit of the answer. 
Result so far: 49940.62
If we take 710 away from 800, we end up with 90.
Since there are no more digits in the dividend, we add a zero to the remainder making it 900, and continue the process.

Let's proceed to step 11:
The number 355 fits into 900 2 times, leaving a remainder of 190.
Write down 2 as next digit of the result. 
Result so far: 49940.622
If we subtract 710 from 900, we get 190.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1900, and continue the process.

The final outcome is 49940.622, with a leftover of 0.019.