400428 ÷ 20 
The aim is to understand the frequency of 20 in 400428.

Let's proceed to step 1:
20 goes into 4 0 times with a remainder of 4.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtracting 0 from 4 leaves us with 4.
Append the next digit (0) from the dividend to 4 and continue with: 40 / 20

Moving on to step 2:
20 goes into 40 2 times with a remainder of 0.
Write down 2 as next digit of the result. 
Result so far: 2.0
The remainder is 0 after subtracting 40 from 40.
Fetch the next digit (0) from the dividend, attach it to 0 and continue: 0 / 20

Step 3:
When dividing 0 by 20, we get 0 with a remainder of 0.
The next digit of our result is 0. 
Result so far: 20.0
The remainder is 0 after subtracting 0 from 0.
Include the next digit (4) from the dividend after 0, then repeat: 4 / 20

Advancing to step 4:
4 divided by 20 is 0 with a remainder of 4.
Put 0 as the next digit of the answer. 
Result so far: 200.0
Deduct 0 from 4 and we're left with 4.
Bring next digit (2) of the dividend behind the 4 and repeat the process: 42 / 20

Let's proceed to step 5:
42 divided by 20 is 2 with a remainder of 2.
Put 2 as the next digit of the answer. 
Result so far: 2002.0
If we subtract 40 from 42, we get 2.
Take the next digit (8) from the dividend and append it to 2, then repeat: 28 / 20

Going ahead to step 6:
If we divide 28 by 20, we get 1 and a remainder of 8.
The number 1 becomes the next digit in our result. 
Result so far: 20021.0
If we take 20 away from 28, we end up with 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Step 7:
If we divide 80 by 20, we get 4 and a remainder of 0.
Put 4 as the next digit of the answer. 
Result so far: 20021.4
Subtract 80 from 80 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.
Write down 0 as next digit of the result. 
Result so far: 20021.4
If we take 0 away from 0, we end up 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 9:
0 divided by 20 is 0 with a remainder of 0.
The number 0 becomes the next digit in our result. 
Result so far: 20021.4
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 final outcome is 20021.4, with a leftover of 0.0.