765579 ÷ 66 
The aim is to understand the frequency of 66 in 765579.

Advancing to step 1:
66 goes into 7 0 times with a remainder of 7.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we subtract 0 from 7, we get 7.
Grab the next digit (6) from the dividend, add it to 7, then carry on: 76 / 66

Moving on to step 2:
76 divided by 66 is 1 with a remainder of 10.
The next digit of our result is 1. 
Result so far: 1.0
Deduct 66 from 76 and we're left with 10.
Include the next digit (5) from the dividend after 10, then repeat: 105 / 66

Moving on to step 3:
105 divided by 66 is 1 with a remainder of 39.
Use 1 as the next digit of our solution. 
Result so far: 11.0
If we subtract 66 from 105, we get 39.
Grab the next digit (5) from the dividend, add it to 39, then carry on: 395 / 66

Let's proceed to step 4:
66 can be fit into 395 5 times, resulting in a remainder of 65.
Use 5 as the next digit of our solution. 
Result so far: 115.0
If we take 330 away from 395, we end up with 65.
Bring next digit (7) of the dividend behind the 65 and repeat the process: 657 / 66

Going ahead to step 5:
If we divide 657 by 66, we get 9 and a remainder of 63.
Write down 9 as next digit of the result. 
Result so far: 1159.0
If we subtract 594 from 657, we get 63.
Take the next digit (9) from the dividend and append it to 63, then repeat: 639 / 66

On to step 6:
When dividing 639 by 66, we get 9 with a remainder of 45.
Use 9 as the next digit of our solution. 
Result so far: 11599.0
The remainder is 45 after subtracting 594 from 639.
Since there are no more digits in the dividend, we add a zero to the remainder making it 450, and continue the process.

Advancing to step 7:
When dividing 450 by 66, we get 6 with a remainder of 54.
The number 6 becomes the next digit in our result. 
Result so far: 11599.6
If we subtract 396 from 450, we get 54.
Since there are no more digits in the dividend, we add a zero to the remainder making it 540, and continue the process.

On to step 8:
66 can be fit into 540 8 times, resulting in a remainder of 12.
Put 8 as the next digit of the answer. 
Result so far: 11599.68
Subtract 528 from 540 to get 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Moving on to step 9:
66 can be fit into 120 1 times, resulting in a remainder of 54.
Record the quotient 1 as the next digit in the result. 
Result so far: 11599.681
If we take 66 away from 120, 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.

On to step 10:
When dividing 540 by 66, we get 8 with a remainder of 12.
Write down 8 as next digit of the result. 
Result so far: 11599.6818
If we take 528 away from 540, we end up with 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Step 11:
120 divided by 66 is 1 with a remainder of 54.
The number 1 becomes the next digit in our result. 
Result so far: 11599.68181
Subtract 66 from 120 to get 54.
Since there are no more digits in the dividend, we add a zero to the remainder making it 540, and continue the process.

Advancing to step 12:
66 can be fit into 540 8 times, resulting in a remainder of 12.
The next digit of our result is 8. 
Result so far: 11599.681818
Subtracting 528 from 540 leaves us with 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Advancing to step 13:
The number 66 fits into 120 1 times, leaving a remainder of 54.
Write down 1 as next digit of the result. 
Result so far: 11599.6818181
If we subtract 66 from 120, we get 54.
Since there are no more digits in the dividend, we add a zero to the remainder making it 540, and continue the process.

Moving on to step 14:
540 divided by 66 is 8 with a remainder of 12.
Write down 8 as next digit of the result. 
Result so far: 11599.68181818
The remainder is 12 after subtracting 528 from 540.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

The final outcome is 11599.68181818, with a leftover of 1.2e-08.