640809 ÷ 18 
Our goal is to divide 640809 by 18.

On to step 1:
18 can be fit into 6 0 times, resulting in a remainder of 6.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we take 0 away from 6, we end up with 6.
Include the next digit (4) from the dividend after 6, then repeat: 64 / 18

Step 2:
When dividing 64 by 18, we get 3 with a remainder of 10.
Write down 3 as next digit of the result. 
Result so far: 3.0
The remainder is 10 after subtracting 54 from 64.
Include the next digit (0) from the dividend after 10, then repeat: 100 / 18

Let's proceed to step 3:
If we divide 100 by 18, we get 5 and a remainder of 10.
The number 5 becomes the next digit in our result. 
Result so far: 35.0
The remainder is 10 after subtracting 90 from 100.
Take the next digit (8) from the dividend and append it to 10, then repeat: 108 / 18

Going ahead to step 4:
18 goes into 108 6 times with a remainder of 0.
Write down 6 as next digit of the result. 
Result so far: 356.0
If we subtract 108 from 108, we get 0.
Append the next digit (0) from the dividend to 0 and continue with: 0 / 18

Advancing to step 5:
The number 18 fits into 0 0 times, leaving a remainder of 0.
Record the quotient 0 as the next digit in the result. 
Result so far: 3560.0
If we subtract 0 from 0, we get 0.
Fetch the next digit (9) from the dividend, attach it to 0 and continue: 9 / 18

Let's proceed to step 6:
The number 18 fits into 9 0 times, leaving a remainder of 9.
Record the quotient 0 as the next digit in the result. 
Result so far: 35600.0
Deduct 0 from 9 and we're left with 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

Let's proceed to step 7:
When dividing 90 by 18, we get 5 with a remainder of 0.
Use 5 as the next digit of our solution. 
Result so far: 35600.5
If we take 90 away from 90, 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 8:
If we divide 0 by 18, we get 0 and a remainder of 0.
Record the quotient 0 as the next digit in the result. 
Result so far: 35600.5
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.

Moving on to step 9:
If we divide 0 by 18, we get 0 and a remainder of 0.
Put 0 as the next digit of the answer. 
Result so far: 35600.5
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 35600.5 and a remainder of 0.0.