We're dividing 90819906 by 866 
The aim is to understand the frequency of 866 in 90819906.

Advancing to step 1:
If we divide 9 by 866, we get 0 and a remainder of 9.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtracting 0 from 9 leaves us with 9.
Fetch the next digit (0) from the dividend, attach it to 9 and continue: 90 / 866

Let's proceed to step 2:
The number 866 fits into 90 0 times, leaving a remainder of 90.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we subtract 0 from 90, we get 90.
Append the next digit (8) from the dividend to 90 and continue with: 908 / 866

Going ahead to step 3:
If we divide 908 by 866, we get 1 and a remainder of 42.
Record the quotient 1 as the next digit in the result. 
Result so far: 1.0
Subtract 866 from 908 to get 42.
Grab the next digit (1) from the dividend, add it to 42, then carry on: 421 / 866

Step 4:
866 goes into 421 0 times with a remainder of 421.
The next digit of our result is 0. 
Result so far: 10.0
If we take 0 away from 421, we end up with 421.
Take the next digit (9) from the dividend and append it to 421, then repeat: 4219 / 866

Going ahead to step 5:
866 can be fit into 4219 4 times, resulting in a remainder of 755.
Record the quotient 4 as the next digit in the result. 
Result so far: 104.0
The remainder is 755 after subtracting 3464 from 4219.
Fetch the next digit (9) from the dividend, attach it to 755 and continue: 7559 / 866

Let's proceed to step 6:
866 goes into 7559 8 times with a remainder of 631.
Put 8 as the next digit of the answer. 
Result so far: 1048.0
If we take 6928 away from 7559, we end up with 631.
Take the next digit (0) from the dividend and append it to 631, then repeat: 6310 / 866

Let's proceed to step 7:
If we divide 6310 by 866, we get 7 and a remainder of 248.
Record the quotient 7 as the next digit in the result. 
Result so far: 10487.0
The remainder is 248 after subtracting 6062 from 6310.
Bring next digit (6) of the dividend behind the 248 and repeat the process: 2486 / 866

Let's proceed to step 8:
2486 divided by 866 is 2 with a remainder of 754.
The next digit of our result is 2. 
Result so far: 104872.0
Deduct 1732 from 2486 and we're left with 754.
Since there are no more digits in the dividend, we add a zero to the remainder making it 7540, and continue the process.

Going ahead to step 9:
If we divide 7540 by 866, we get 8 and a remainder of 612.
Put 8 as the next digit of the answer. 
Result so far: 104872.8
The remainder is 612 after subtracting 6928 from 7540.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6120, and continue the process.

Let's proceed to step 10:
866 goes into 6120 7 times with a remainder of 58.
Use 7 as the next digit of our solution. 
Result so far: 104872.87
If we take 6062 away from 6120, we end up with 58.
Since there are no more digits in the dividend, we add a zero to the remainder making it 580, and continue the process.

Step 11:
When dividing 580 by 866, we get 0 with a remainder of 580.
The next digit of our result is 0. 
Result so far: 104872.87
Subtract 0 from 580 to get 580.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5800, and continue the process.

Let's proceed to step 12:
When dividing 5800 by 866, we get 6 with a remainder of 604.
Write down 6 as next digit of the result. 
Result so far: 104872.8706
The remainder is 604 after subtracting 5196 from 5800.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6040, and continue the process.

Let's proceed to step 13:
The number 866 fits into 6040 6 times, leaving a remainder of 844.
The number 6 becomes the next digit in our result. 
Result so far: 104872.87066
If we subtract 5196 from 6040, we get 844.
Since there are no more digits in the dividend, we add a zero to the remainder making it 8440, and continue the process.

After the division, we end up with 104872.87066 and a remainder of 0.000844.