We look at the division of 661655 by 30 
The aim is to understand the frequency of 30 in 661655.

Step 1:
When dividing 6 by 30, we get 0 with a remainder of 6.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtract 0 from 6 to get 6.
Bring next digit (6) of the dividend behind the 6 and repeat the process: 66 / 30

Step 2:
66 divided by 30 is 2 with a remainder of 6.
Record the quotient 2 as the next digit in the result. 
Result so far: 2.0
If we subtract 60 from 66, we get 6.
Fetch the next digit (1) from the dividend, attach it to 6 and continue: 61 / 30

On to step 3:
If we divide 61 by 30, we get 2 and a remainder of 1.
Put 2 as the next digit of the answer. 
Result so far: 22.0
Subtract 60 from 61 to get 1.
Append the next digit (6) from the dividend to 1 and continue with: 16 / 30

Let's proceed to step 4:
30 can be fit into 16 0 times, resulting in a remainder of 16.
Record the quotient 0 as the next digit in the result. 
Result so far: 220.0
Subtract 0 from 16 to get 16.
Append the next digit (5) from the dividend to 16 and continue with: 165 / 30

Going ahead to step 5:
30 goes into 165 5 times with a remainder of 15.
Record the quotient 5 as the next digit in the result. 
Result so far: 2205.0
Deduct 150 from 165 and we're left with 15.
Append the next digit (5) from the dividend to 15 and continue with: 155 / 30

Going ahead to step 6:
When dividing 155 by 30, we get 5 with a remainder of 5.
The number 5 becomes the next digit in our result. 
Result so far: 22055.0
The remainder is 5 after subtracting 150 from 155.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Going ahead to step 7:
If we divide 50 by 30, we get 1 and a remainder of 20.
Use 1 as the next digit of our solution. 
Result so far: 22055.1
If we take 30 away from 50, we end up with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Step 8:
When dividing 200 by 30, we get 6 with a remainder of 20.
Put 6 as the next digit of the answer. 
Result so far: 22055.16
If we take 180 away from 200, we end up with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Going ahead to step 9:
30 can be fit into 200 6 times, resulting in a remainder of 20.
Put 6 as the next digit of the answer. 
Result so far: 22055.166
If we take 180 away from 200, we end up with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

The quotient of the division is 22055.166, and the remainder is 0.002.