660513 ÷ 20 
The aim is to understand the frequency of 20 in 660513.

On to step 1:
20 goes into 6 0 times 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.
Append the next digit (6) from the dividend to 6 and continue with: 66 / 20

Advancing to step 2:
When dividing 66 by 20, we get 3 with a remainder of 6.
Write down 3 as next digit of the result. 
Result so far: 3.0
Subtracting 60 from 66 leaves us with 6.
Bring next digit (0) of the dividend behind the 6 and repeat the process: 60 / 20

Moving on to step 3:
When dividing 60 by 20, we get 3 with a remainder of 0.
Write down 3 as next digit of the result. 
Result so far: 33.0
The remainder is 0 after subtracting 60 from 60.
Include the next digit (5) from the dividend after 0, then repeat: 5 / 20

Moving on to step 4:
20 goes into 5 0 times with a remainder of 5.
The number 0 becomes the next digit in our result. 
Result so far: 330.0
Subtract 0 from 5 to get 5.
Grab the next digit (1) from the dividend, add it to 5, then carry on: 51 / 20

Going ahead to step 5:
51 divided by 20 is 2 with a remainder of 11.
Use 2 as the next digit of our solution. 
Result so far: 3302.0
Subtract 40 from 51 to get 11.
Grab the next digit (3) from the dividend, add it to 11, then carry on: 113 / 20

Advancing to step 6:
The number 20 fits into 113 5 times, leaving a remainder of 13.
Put 5 as the next digit of the answer. 
Result so far: 33025.0
Subtracting 100 from 113 leaves us with 13.
Since there are no more digits in the dividend, we add a zero to the remainder making it 130, and continue the process.

Advancing to step 7:
20 can be fit into 130 6 times, resulting in a remainder of 10.
Write down 6 as next digit of the result. 
Result so far: 33025.6
Deduct 120 from 130 and we're left with 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

On to step 8:
The number 20 fits into 100 5 times, leaving a remainder of 0.
The number 5 becomes the next digit in our result. 
Result so far: 33025.65
If we subtract 100 from 100, we get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Step 9:
20 goes into 0 0 times with a remainder of 0.
Use 0 as the next digit of our solution. 
Result so far: 33025.65
Subtracting 0 from 0 leaves us with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Going ahead to step 10:
20 goes into 0 0 times with a remainder of 0.
Use 0 as the next digit of our solution. 
Result so far: 33025.65
The remainder is 0 after subtracting 0 from 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

The final outcome is 33025.65, with a leftover of 0.0.