866199 ÷ 77 
The aim is to understand the frequency of 77 in 866199.

Advancing to step 1:
If we divide 8 by 77, we get 0 and a remainder of 8.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
If we take 0 away from 8, we end up with 8.
Take the next digit (6) from the dividend and append it to 8, then repeat: 86 / 77

Step 2:
The number 77 fits into 86 1 times, leaving a remainder of 9.
Put 1 as the next digit of the answer. 
Result so far: 1.0
If we take 77 away from 86, we end up with 9.
Include the next digit (6) from the dividend after 9, then repeat: 96 / 77

Going ahead to step 3:
77 can be fit into 96 1 times, resulting in a remainder of 19.
Put 1 as the next digit of the answer. 
Result so far: 11.0
If we take 77 away from 96, we end up with 19.
Grab the next digit (1) from the dividend, add it to 19, then carry on: 191 / 77

Advancing to step 4:
If we divide 191 by 77, we get 2 and a remainder of 37.
The next digit of our result is 2. 
Result so far: 112.0
If we take 154 away from 191, we end up with 37.
Grab the next digit (9) from the dividend, add it to 37, then carry on: 379 / 77

Going ahead to step 5:
379 divided by 77 is 4 with a remainder of 71.
The number 4 becomes the next digit in our result. 
Result so far: 1124.0
Subtracting 308 from 379 leaves us with 71.
Bring next digit (9) of the dividend behind the 71 and repeat the process: 719 / 77

Step 6:
719 divided by 77 is 9 with a remainder of 26.
Write down 9 as next digit of the result. 
Result so far: 11249.0
Deduct 693 from 719 and we're left with 26.
Since there are no more digits in the dividend, we add a zero to the remainder making it 260, and continue the process.

Advancing to step 7:
The number 77 fits into 260 3 times, leaving a remainder of 29.
Write down 3 as next digit of the result. 
Result so far: 11249.3
Subtract 231 from 260 to get 29.
Since there are no more digits in the dividend, we add a zero to the remainder making it 290, and continue the process.

Moving on to step 8:
77 can be fit into 290 3 times, resulting in a remainder of 59.
Use 3 as the next digit of our solution. 
Result so far: 11249.33
Subtract 231 from 290 to get 59.
Since there are no more digits in the dividend, we add a zero to the remainder making it 590, and continue the process.

The final outcome is 11249.33, with a leftover of 0.059.