We're dividing 353009 by 66 
The aim is to understand the frequency of 66 in 353009.

Advancing to step 1:
66 can be fit into 3 0 times, resulting in a remainder of 3.
The next digit of our result is 0. 
Result so far: 0.0
If we take 0 away from 3, we end up with 3.
Take the next digit (5) from the dividend and append it to 3, then repeat: 35 / 66

Moving on to step 2:
When dividing 35 by 66, we get 0 with a remainder of 35.
Use 0 as the next digit of our solution. 
Result so far: 0.0
The remainder is 35 after subtracting 0 from 35.
Take the next digit (3) from the dividend and append it to 35, then repeat: 353 / 66

Moving on to step 3:
66 goes into 353 5 times with a remainder of 23.
The next digit of our result is 5. 
Result so far: 5.0
If we take 330 away from 353, we end up with 23.
Append the next digit (0) from the dividend to 23 and continue with: 230 / 66

Let's proceed to step 4:
66 can be fit into 230 3 times, resulting in a remainder of 32.
Record the quotient 3 as the next digit in the result. 
Result so far: 53.0
Deduct 198 from 230 and we're left with 32.
Bring next digit (0) of the dividend behind the 32 and repeat the process: 320 / 66

On to step 5:
The number 66 fits into 320 4 times, leaving a remainder of 56.
Write down 4 as next digit of the result. 
Result so far: 534.0
The remainder is 56 after subtracting 264 from 320.
Take the next digit (9) from the dividend and append it to 56, then repeat: 569 / 66

Advancing to step 6:
569 divided by 66 is 8 with a remainder of 41.
The number 8 becomes the next digit in our result. 
Result so far: 5348.0
If we take 528 away from 569, we end up with 41.
Since there are no more digits in the dividend, we add a zero to the remainder making it 410, and continue the process.

On to step 7:
If we divide 410 by 66, we get 6 and a remainder of 14.
Record the quotient 6 as the next digit in the result. 
Result so far: 5348.6
The remainder is 14 after subtracting 396 from 410.
Since there are no more digits in the dividend, we add a zero to the remainder making it 140, and continue the process.

Step 8:
If we divide 140 by 66, we get 2 and a remainder of 8.
Use 2 as the next digit of our solution. 
Result so far: 5348.62
Subtracting 132 from 140 leaves us with 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Moving on to step 9:
80 divided by 66 is 1 with a remainder of 14.
Write down 1 as next digit of the result. 
Result so far: 5348.621
Subtracting 66 from 80 leaves us with 14.
Since there are no more digits in the dividend, we add a zero to the remainder making it 140, and continue the process.

Moving on to step 10:
The number 66 fits into 140 2 times, leaving a remainder of 8.
Put 2 as the next digit of the answer. 
Result so far: 5348.6212
Subtract 132 from 140 to get 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Let's proceed to step 11:
If we divide 80 by 66, we get 1 and a remainder of 14.
Use 1 as the next digit of our solution. 
Result so far: 5348.62121
The remainder is 14 after subtracting 66 from 80.
Since there are no more digits in the dividend, we add a zero to the remainder making it 140, and continue the process.

On to step 12:
66 goes into 140 2 times with a remainder of 8.
Write down 2 as next digit of the result. 
Result so far: 5348.621212
Deduct 132 from 140 and we're left with 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Let's proceed to step 13:
If we divide 80 by 66, we get 1 and a remainder of 14.
The number 1 becomes the next digit in our result. 
Result so far: 5348.6212121
Deduct 66 from 80 and we're left with 14.
Since there are no more digits in the dividend, we add a zero to the remainder making it 140, and continue the process.

Going ahead to step 14:
140 divided by 66 is 2 with a remainder of 8.
Put 2 as the next digit of the answer. 
Result so far: 5348.62121212
Subtract 132 from 140 to get 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Our division results in 5348.62121212 with a remaining 8e-09.