We look at the division of 509268 by 20 
The aim is to understand the frequency of 20 in 509268.

On to step 1:
20 goes into 5 0 times with a remainder of 5.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtracting 0 from 5 leaves us with 5.
Fetch the next digit (0) from the dividend, attach it to 5 and continue: 50 / 20

Moving on to step 2:
20 can be fit into 50 2 times, resulting in a remainder of 10.
Record the quotient 2 as the next digit in the result. 
Result so far: 2.0
Subtract 40 from 50 to get 10.
Fetch the next digit (9) from the dividend, attach it to 10 and continue: 109 / 20

Advancing to step 3:
20 can be fit into 109 5 times, resulting in a remainder of 9.
Write down 5 as next digit of the result. 
Result so far: 25.0
Subtract 100 from 109 to get 9.
Append the next digit (2) from the dividend to 9 and continue with: 92 / 20

On to step 4:
20 can be fit into 92 4 times, resulting in a remainder of 12.
Record the quotient 4 as the next digit in the result. 
Result so far: 254.0
If we subtract 80 from 92, we get 12.
Include the next digit (6) from the dividend after 12, then repeat: 126 / 20

Step 5:
When dividing 126 by 20, we get 6 with a remainder of 6.
Put 6 as the next digit of the answer. 
Result so far: 2546.0
If we take 120 away from 126, we end up with 6.
Take the next digit (8) from the dividend and append it to 6, then repeat: 68 / 20

Let's proceed to step 6:
68 divided by 20 is 3 with a remainder of 8.
Record the quotient 3 as the next digit in the result. 
Result so far: 25463.0
Subtract 60 from 68 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.

Going ahead to step 7:
20 can be fit into 80 4 times, resulting in a remainder of 0.
Use 4 as the next digit of our solution. 
Result so far: 25463.4
If we subtract 80 from 80, 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.

Advancing to step 8:
When dividing 0 by 20, we get 0 with a remainder of 0.
The number 0 becomes the next digit in our result. 
Result so far: 25463.4
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.

Moving on to step 9:
20 goes into 0 0 times with a remainder of 0.
Record the quotient 0 as the next digit in the result. 
Result so far: 25463.4
Deduct 0 from 0 and we're left 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.

The quotient of the division is 25463.4, and the remainder is 0.0.