643749 ÷ 65 
The aim is to understand the frequency of 65 in 643749.

On to step 1:
The number 65 fits into 6 0 times, leaving a remainder of 6.
Write down 0 as next digit of the result. 
Result so far: 0.0
The remainder is 6 after subtracting 0 from 6.
Fetch the next digit (4) from the dividend, attach it to 6 and continue: 64 / 65

Moving on to step 2:
If we divide 64 by 65, we get 0 and a remainder of 64.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we take 0 away from 64, we end up with 64.
Fetch the next digit (3) from the dividend, attach it to 64 and continue: 643 / 65

Let's proceed to step 3:
The number 65 fits into 643 9 times, leaving a remainder of 58.
The next digit of our result is 9. 
Result so far: 9.0
If we take 585 away from 643, we end up with 58.
Fetch the next digit (7) from the dividend, attach it to 58 and continue: 587 / 65

On to step 4:
65 can be fit into 587 9 times, resulting in a remainder of 2.
Record the quotient 9 as the next digit in the result. 
Result so far: 99.0
Subtracting 585 from 587 leaves us with 2.
Grab the next digit (4) from the dividend, add it to 2, then carry on: 24 / 65

Moving on to step 5:
65 can be fit into 24 0 times, resulting in a remainder of 24.
Use 0 as the next digit of our solution. 
Result so far: 990.0
The remainder is 24 after subtracting 0 from 24.
Append the next digit (9) from the dividend to 24 and continue with: 249 / 65

Let's proceed to step 6:
The number 65 fits into 249 3 times, leaving a remainder of 54.
The next digit of our result is 3. 
Result so far: 9903.0
If we take 195 away from 249, we end up with 54.
Since there are no more digits in the dividend, we add a zero to the remainder making it 540, and continue the process.

Step 7:
65 can be fit into 540 8 times, resulting in a remainder of 20.
The next digit of our result is 8. 
Result so far: 9903.8
Deduct 520 from 540 and we're left with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Step 8:
65 can be fit into 200 3 times, resulting in a remainder of 5.
Put 3 as the next digit of the answer. 
Result so far: 9903.83
If we subtract 195 from 200, we get 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Going ahead to step 9:
50 divided by 65 is 0 with a remainder of 50.
The next digit of our result is 0. 
Result so far: 9903.83
If we take 0 away from 50, we end up with 50.
Since there are no more digits in the dividend, we add a zero to the remainder making it 500, and continue the process.

Advancing to step 10:
If we divide 500 by 65, we get 7 and a remainder of 45.
The number 7 becomes the next digit in our result. 
Result so far: 9903.8307
If we take 455 away from 500, we end up with 45.
Since there are no more digits in the dividend, we add a zero to the remainder making it 450, and continue the process.

Let's proceed to step 11:
65 goes into 450 6 times with a remainder of 60.
Record the quotient 6 as the next digit in the result. 
Result so far: 9903.83076
Subtract 390 from 450 to get 60.
Since there are no more digits in the dividend, we add a zero to the remainder making it 600, and continue the process.

Advancing to step 12:
If we divide 600 by 65, we get 9 and a remainder of 15.
The number 9 becomes the next digit in our result. 
Result so far: 9903.830769
The remainder is 15 after subtracting 585 from 600.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

Let's proceed to step 13:
65 goes into 150 2 times with a remainder of 20.
Record the quotient 2 as the next digit in the result. 
Result so far: 9903.8307692
If we take 130 away from 150, we end up with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Advancing to step 14:
65 can be fit into 200 3 times, resulting in a remainder of 5.
The number 3 becomes the next digit in our result. 
Result so far: 9903.83076923
The remainder is 5 after subtracting 195 from 200.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

The final result is 9903.83076923 with a remainder of 5e-09.