We look at the division of 810066 by 66 
The aim is to understand the frequency of 66 in 810066.

Step 1:
8 divided by 66 is 0 with a remainder of 8.
The next digit of our result is 0. 
Result so far: 0.0
If we subtract 0 from 8, we get 8.
Bring next digit (1) of the dividend behind the 8 and repeat the process: 81 / 66

Going ahead to step 2:
66 can be fit into 81 1 times, resulting in a remainder of 15.
The next digit of our result is 1. 
Result so far: 1.0
Subtract 66 from 81 to get 15.
Fetch the next digit (0) from the dividend, attach it to 15 and continue: 150 / 66

On to step 3:
The number 66 fits into 150 2 times, leaving a remainder of 18.
Write down 2 as next digit of the result. 
Result so far: 12.0
If we subtract 132 from 150, we get 18.
Bring next digit (0) of the dividend behind the 18 and repeat the process: 180 / 66

Moving on to step 4:
The number 66 fits into 180 2 times, leaving a remainder of 48.
The next digit of our result is 2. 
Result so far: 122.0
The remainder is 48 after subtracting 132 from 180.
Include the next digit (6) from the dividend after 48, then repeat: 486 / 66

Moving on to step 5:
66 goes into 486 7 times with a remainder of 24.
The next digit of our result is 7. 
Result so far: 1227.0
The remainder is 24 after subtracting 462 from 486.
Take the next digit (6) from the dividend and append it to 24, then repeat: 246 / 66

Going ahead to step 6:
When dividing 246 by 66, we get 3 with a remainder of 48.
The next digit of our result is 3. 
Result so far: 12273.0
The remainder is 48 after subtracting 198 from 246.
Since there are no more digits in the dividend, we add a zero to the remainder making it 480, and continue the process.

Going ahead to step 7:
When dividing 480 by 66, we get 7 with a remainder of 18.
Use 7 as the next digit of our solution. 
Result so far: 12273.7
Subtract 462 from 480 to get 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

Going ahead to step 8:
180 divided by 66 is 2 with a remainder of 48.
The next digit of our result is 2. 
Result so far: 12273.72
The remainder is 48 after subtracting 132 from 180.
Since there are no more digits in the dividend, we add a zero to the remainder making it 480, and continue the process.

Step 9:
480 divided by 66 is 7 with a remainder of 18.
The next digit of our result is 7. 
Result so far: 12273.727
Deduct 462 from 480 and we're left with 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

On to step 10:
If we divide 180 by 66, we get 2 and a remainder of 48.
The next digit of our result is 2. 
Result so far: 12273.7272
Subtracting 132 from 180 leaves us with 48.
Since there are no more digits in the dividend, we add a zero to the remainder making it 480, and continue the process.

Step 11:
The number 66 fits into 480 7 times, leaving a remainder of 18.
The next digit of our result is 7. 
Result so far: 12273.72727
Deduct 462 from 480 and we're left with 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

Moving on to step 12:
66 can be fit into 180 2 times, resulting in a remainder of 48.
The next digit of our result is 2. 
Result so far: 12273.727272
Subtracting 132 from 180 leaves us with 48.
Since there are no more digits in the dividend, we add a zero to the remainder making it 480, and continue the process.

Moving on to step 13:
The number 66 fits into 480 7 times, leaving a remainder of 18.
Put 7 as the next digit of the answer. 
Result so far: 12273.7272727
The remainder is 18 after subtracting 462 from 480.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

Going ahead to step 14:
66 can be fit into 180 2 times, resulting in a remainder of 48.
Use 2 as the next digit of our solution. 
Result so far: 12273.72727272
Subtracting 132 from 180 leaves us with 48.
Since there are no more digits in the dividend, we add a zero to the remainder making it 480, and continue the process.

The final outcome is 12273.72727272, with a leftover of 4.8e-08.