256170 ÷ 20 
The aim is to understand the frequency of 20 in 256170.

Advancing to step 1:
2 divided by 20 is 0 with a remainder of 2.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 2, we end up with 2.
Include the next digit (5) from the dividend after 2, then repeat: 25 / 20

Going ahead to step 2:
When dividing 25 by 20, we get 1 with a remainder of 5.
The number 1 becomes the next digit in our result. 
Result so far: 1.0
If we subtract 20 from 25, we get 5.
Bring next digit (6) of the dividend behind the 5 and repeat the process: 56 / 20

Moving on to step 3:
56 divided by 20 is 2 with a remainder of 16.
The number 2 becomes the next digit in our result. 
Result so far: 12.0
Deduct 40 from 56 and we're left with 16.
Include the next digit (1) from the dividend after 16, then repeat: 161 / 20

Step 4:
The number 20 fits into 161 8 times, leaving a remainder of 1.
Put 8 as the next digit of the answer. 
Result so far: 128.0
If we take 160 away from 161, we end up with 1.
Fetch the next digit (7) from the dividend, attach it to 1 and continue: 17 / 20

Step 5:
17 divided by 20 is 0 with a remainder of 17.
Write down 0 as next digit of the result. 
Result so far: 1280.0
If we subtract 0 from 17, we get 17.
Include the next digit (0) from the dividend after 17, then repeat: 170 / 20

Moving on to step 6:
170 divided by 20 is 8 with a remainder of 10.
Put 8 as the next digit of the answer. 
Result so far: 12808.0
The remainder is 10 after subtracting 160 from 170.
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 7:
If we divide 100 by 20, we get 5 and a remainder of 0.
Write down 5 as next digit of the result. 
Result so far: 12808.5
Subtract 100 from 100 to 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:
20 can be fit into 0 0 times, resulting in a remainder of 0.
Record the quotient 0 as the next digit in the result. 
Result so far: 12808.5
Subtract 0 from 0 to 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.

On to step 9:
When dividing 0 by 20, we get 0 with a remainder of 0.
Record the quotient 0 as the next digit in the result. 
Result so far: 12808.5
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 final outcome is 12808.5, with a leftover of 0.0.