Let's divide 127645 by 321
The aim is to understand the frequency of 321 in 127645.

On to step 1:
321 goes into 1 0 times with a remainder of 1.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we take 0 away from 1, we end up with 1.
Take the next digit (2) from the dividend and append it to 1, then repeat: 12 / 321

Advancing to step 2:
12 divided by 321 is 0 with a remainder of 12.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we take 0 away from 12, we end up with 12.
Bring next digit (7) of the dividend behind the 12 and repeat the process: 127 / 321

Let's proceed to step 3:
127 divided by 321 is 0 with a remainder of 127.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtract 0 from 127 to get 127.
Bring next digit (6) of the dividend behind the 127 and repeat the process: 1276 / 321

Let's proceed to step 4:
The number 321 fits into 1276 3 times, leaving a remainder of 313.
Record the quotient 3 as the next digit in the result. 
Result so far: 3.0
Subtracting 963 from 1276 leaves us with 313.
Bring next digit (4) of the dividend behind the 313 and repeat the process: 3134 / 321

Advancing to step 5:
321 goes into 3134 9 times with a remainder of 245.
The next digit of our result is 9. 
Result so far: 39.0
If we take 2889 away from 3134, we end up with 245.
Take the next digit (5) from the dividend and append it to 245, then repeat: 2455 / 321

Step 6:
If we divide 2455 by 321, we get 7 and a remainder of 208.
Write down 7 as next digit of the result. 
Result so far: 397.0
Subtract 2247 from 2455 to get 208.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2080, and continue the process.

On to step 7:
321 goes into 2080 6 times with a remainder of 154.
Record the quotient 6 as the next digit in the result. 
Result so far: 397.6
If we subtract 1926 from 2080, we get 154.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1540, and continue the process.

Step 8:
321 can be fit into 1540 4 times, resulting in a remainder of 256.
Put 4 as the next digit of the answer. 
Result so far: 397.64
Subtracting 1284 from 1540 leaves us with 256.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2560, and continue the process.

Advancing to step 9:
321 can be fit into 2560 7 times, resulting in a remainder of 313.
The next digit of our result is 7. 
Result so far: 397.647
If we take 2247 away from 2560, we end up with 313.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3130, and continue the process.

Moving on to step 10:
The number 321 fits into 3130 9 times, leaving a remainder of 241.
The number 9 becomes the next digit in our result. 
Result so far: 397.6479
The remainder is 241 after subtracting 2889 from 3130.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2410, and continue the process.

Going ahead to step 11:
321 goes into 2410 7 times with a remainder of 163.
The number 7 becomes the next digit in our result. 
Result so far: 397.64797
If we take 2247 away from 2410, we end up with 163.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1630, and continue the process.

Advancing to step 12:
When dividing 1630 by 321, we get 5 with a remainder of 25.
The number 5 becomes the next digit in our result. 
Result so far: 397.647975
If we take 1605 away from 1630, we end up with 25.
Since there are no more digits in the dividend, we add a zero to the remainder making it 250, and continue the process.

Going ahead to step 13:
When dividing 250 by 321, we get 0 with a remainder of 250.
The number 0 becomes the next digit in our result. 
Result so far: 397.647975
The remainder is 250 after subtracting 0 from 250.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2500, and continue the process.

Advancing to step 14:
The number 321 fits into 2500 7 times, leaving a remainder of 253.
Record the quotient 7 as the next digit in the result. 
Result so far: 397.64797507
Subtract 2247 from 2500 to get 253.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2530, and continue the process.

The final result is 397.64797507 with a remainder of 2.53e-07.