We look at the division of 661209 by 33 
The aim is to understand the frequency of 33 in 661209.

Going ahead to step 1:
6 divided by 33 is 0 with a remainder of 6.
Write down 0 as next digit of the result. 
Result so far: 0.0
Deduct 0 from 6 and we're left with 6.
Append the next digit (6) from the dividend to 6 and continue with: 66 / 33

On to step 2:
If we divide 66 by 33, we get 2 and a remainder of 0.
Put 2 as the next digit of the answer. 
Result so far: 2.0
Subtract 66 from 66 to get 0.
Fetch the next digit (1) from the dividend, attach it to 0 and continue: 1 / 33

Let's proceed to step 3:
33 goes into 1 0 times with a remainder of 1.
The next digit of our result is 0. 
Result so far: 20.0
If we subtract 0 from 1, we get 1.
Fetch the next digit (2) from the dividend, attach it to 1 and continue: 12 / 33

Let's proceed to step 4:
33 can be fit into 12 0 times, resulting in a remainder of 12.
Write down 0 as next digit of the result. 
Result so far: 200.0
If we subtract 0 from 12, we get 12.
Grab the next digit (0) from the dividend, add it to 12, then carry on: 120 / 33

Let's proceed to step 5:
When dividing 120 by 33, we get 3 with a remainder of 21.
Put 3 as the next digit of the answer. 
Result so far: 2003.0
Deduct 99 from 120 and we're left with 21.
Append the next digit (9) from the dividend to 21 and continue with: 219 / 33

Advancing to step 6:
33 goes into 219 6 times with a remainder of 21.
The number 6 becomes the next digit in our result. 
Result so far: 20036.0
If we take 198 away from 219, we end up with 21.
Since there are no more digits in the dividend, we add a zero to the remainder making it 210, and continue the process.

Advancing to step 7:
33 goes into 210 6 times with a remainder of 12.
Write down 6 as next digit of the result. 
Result so far: 20036.6
Subtract 198 from 210 to get 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

On to step 8:
When dividing 120 by 33, we get 3 with a remainder of 21.
Write down 3 as next digit of the result. 
Result so far: 20036.63
Subtracting 99 from 120 leaves us with 21.
Since there are no more digits in the dividend, we add a zero to the remainder making it 210, and continue the process.

Advancing to step 9:
If we divide 210 by 33, we get 6 and a remainder of 12.
Write down 6 as next digit of the result. 
Result so far: 20036.636
Deduct 198 from 210 and we're left with 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Let's proceed to step 10:
120 divided by 33 is 3 with a remainder of 21.
The next digit of our result is 3. 
Result so far: 20036.6363
The remainder is 21 after subtracting 99 from 120.
Since there are no more digits in the dividend, we add a zero to the remainder making it 210, and continue the process.

Going ahead to step 11:
The number 33 fits into 210 6 times, leaving a remainder of 12.
Record the quotient 6 as the next digit in the result. 
Result so far: 20036.63636
Subtract 198 from 210 to get 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Let's proceed to step 12:
If we divide 120 by 33, we get 3 and a remainder of 21.
Write down 3 as next digit of the result. 
Result so far: 20036.636363
Deduct 99 from 120 and we're left with 21.
Since there are no more digits in the dividend, we add a zero to the remainder making it 210, and continue the process.

Let's proceed to step 13:
33 goes into 210 6 times with a remainder of 12.
The number 6 becomes the next digit in our result. 
Result so far: 20036.6363636
If we subtract 198 from 210, we get 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Moving on to step 14:
120 divided by 33 is 3 with a remainder of 21.
The next digit of our result is 3. 
Result so far: 20036.63636363
If we subtract 99 from 120, we get 21.
Since there are no more digits in the dividend, we add a zero to the remainder making it 210, and continue the process.

The final outcome is 20036.63636363, with a leftover of 2.1e-08.