We look at the division of 397646 by 20 
The aim is to understand the frequency of 20 in 397646.

Let's proceed to step 1:
The number 20 fits into 3 0 times, leaving a remainder of 3.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
The remainder is 3 after subtracting 0 from 3.
Append the next digit (9) from the dividend to 3 and continue with: 39 / 20

Let's proceed to step 2:
39 divided by 20 is 1 with a remainder of 19.
Record the quotient 1 as the next digit in the result. 
Result so far: 1.0
Deduct 20 from 39 and we're left with 19.
Grab the next digit (7) from the dividend, add it to 19, then carry on: 197 / 20

On to step 3:
20 goes into 197 9 times with a remainder of 17.
Put 9 as the next digit of the answer. 
Result so far: 19.0
Subtract 180 from 197 to get 17.
Include the next digit (6) from the dividend after 17, then repeat: 176 / 20

On to step 4:
176 divided by 20 is 8 with a remainder of 16.
Record the quotient 8 as the next digit in the result. 
Result so far: 198.0
Deduct 160 from 176 and we're left with 16.
Grab the next digit (4) from the dividend, add it to 16, then carry on: 164 / 20

On to step 5:
When dividing 164 by 20, we get 8 with a remainder of 4.
Write down 8 as next digit of the result. 
Result so far: 1988.0
Subtracting 160 from 164 leaves us with 4.
Grab the next digit (6) from the dividend, add it to 4, then carry on: 46 / 20

Moving on to step 6:
If we divide 46 by 20, we get 2 and a remainder of 6.
Use 2 as the next digit of our solution. 
Result so far: 19882.0
If we subtract 40 from 46, we get 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

On to step 7:
The number 20 fits into 60 3 times, leaving a remainder of 0.
Use 3 as the next digit of our solution. 
Result so far: 19882.3
The remainder is 0 after subtracting 60 from 60.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Let's proceed to step 8:
0 divided by 20 is 0 with a remainder of 0.
Use 0 as the next digit of our solution. 
Result so far: 19882.3
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.

Advancing to step 9:
The number 20 fits into 0 0 times, leaving a remainder of 0.
The number 0 becomes the next digit in our result. 
Result so far: 19882.3
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.

After the division, we end up with 19882.3 and a remainder of 0.0.