We're dividing 423040 by 20 
Let's see how many times 20 fits into 423040.

Let's proceed to step 1:
20 can be fit into 4 0 times, resulting in a remainder of 4.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtract 0 from 4 to get 4.
Take the next digit (2) from the dividend and append it to 4, then repeat: 42 / 20

On to step 2:
The number 20 fits into 42 2 times, leaving a remainder of 2.
Record the quotient 2 as the next digit in the result. 
Result so far: 2.0
If we subtract 40 from 42, we get 2.
Include the next digit (3) from the dividend after 2, then repeat: 23 / 20

Step 3:
When dividing 23 by 20, we get 1 with a remainder of 3.
The number 1 becomes the next digit in our result. 
Result so far: 21.0
If we take 20 away from 23, we end up with 3.
Append the next digit (0) from the dividend to 3 and continue with: 30 / 20

Moving on to step 4:
The number 20 fits into 30 1 times, leaving a remainder of 10.
The number 1 becomes the next digit in our result. 
Result so far: 211.0
Subtract 20 from 30 to get 10.
Bring next digit (4) of the dividend behind the 10 and repeat the process: 104 / 20

Advancing to step 5:
When dividing 104 by 20, we get 5 with a remainder of 4.
Use 5 as the next digit of our solution. 
Result so far: 2115.0
If we take 100 away from 104, we end up with 4.
Take the next digit (0) from the dividend and append it to 4, then repeat: 40 / 20

Let's proceed to step 6:
When dividing 40 by 20, we get 2 with a remainder of 0.
Put 2 as the next digit of the answer. 
Result so far: 21152.0
Subtract 40 from 40 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 7:
0 divided by 20 is 0 with a remainder of 0.
The number 0 becomes the next digit in our result. 
Result so far: 21152.0
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 8:
When dividing 0 by 20, we get 0 with a remainder of 0.
Use 0 as the next digit of our solution. 
Result so far: 21152.0
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 quotient of the division is 21152.0, and the remainder is 0.0.