438955 divided by 66 
The aim is to understand the frequency of 66 in 438955.

Step 1:
When dividing 4 by 66, we get 0 with a remainder of 4.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtract 0 from 4 to get 4.
Append the next digit (3) from the dividend to 4 and continue with: 43 / 66

On to step 2:
The number 66 fits into 43 0 times, leaving a remainder of 43.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 43, we end up with 43.
Fetch the next digit (8) from the dividend, attach it to 43 and continue: 438 / 66

Let's proceed to step 3:
When dividing 438 by 66, we get 6 with a remainder of 42.
The next digit of our result is 6. 
Result so far: 6.0
Subtracting 396 from 438 leaves us with 42.
Take the next digit (9) from the dividend and append it to 42, then repeat: 429 / 66

Let's proceed to step 4:
66 can be fit into 429 6 times, resulting in a remainder of 33.
Write down 6 as next digit of the result. 
Result so far: 66.0
Subtracting 396 from 429 leaves us with 33.
Append the next digit (5) from the dividend to 33 and continue with: 335 / 66

Let's proceed to step 5:
66 can be fit into 335 5 times, resulting in a remainder of 5.
The next digit of our result is 5. 
Result so far: 665.0
Subtracting 330 from 335 leaves us with 5.
Fetch the next digit (5) from the dividend, attach it to 5 and continue: 55 / 66

Moving on to step 6:
If we divide 55 by 66, we get 0 and a remainder of 55.
Record the quotient 0 as the next digit in the result. 
Result so far: 6650.0
Subtracting 0 from 55 leaves us with 55.
Since there are no more digits in the dividend, we add a zero to the remainder making it 550, and continue the process.

Moving on to step 7:
66 goes into 550 8 times with a remainder of 22.
The number 8 becomes the next digit in our result. 
Result so far: 6650.8
The remainder is 22 after subtracting 528 from 550.
Since there are no more digits in the dividend, we add a zero to the remainder making it 220, and continue the process.

Step 8:
If we divide 220 by 66, we get 3 and a remainder of 22.
Record the quotient 3 as the next digit in the result. 
Result so far: 6650.83
If we subtract 198 from 220, we get 22.
Since there are no more digits in the dividend, we add a zero to the remainder making it 220, and continue the process.

Let's proceed to step 9:
66 goes into 220 3 times with a remainder of 22.
Record the quotient 3 as the next digit in the result. 
Result so far: 6650.833
Subtract 198 from 220 to get 22.
Since there are no more digits in the dividend, we add a zero to the remainder making it 220, and continue the process.

Our division results in 6650.833 with a remaining 0.0022.