We're dividing 743209 by 40 
We want to figure out the number of times 743209 can be divided by 40.

On to step 1:
7 divided by 40 is 0 with a remainder of 7.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we subtract 0 from 7, we get 7.
Fetch the next digit (4) from the dividend, attach it to 7 and continue: 74 / 40

On to step 2:
40 can be fit into 74 1 times, resulting in a remainder of 34.
Put 1 as the next digit of the answer. 
Result so far: 1.0
Subtracting 40 from 74 leaves us with 34.
Append the next digit (3) from the dividend to 34 and continue with: 343 / 40

Step 3:
When dividing 343 by 40, we get 8 with a remainder of 23.
Use 8 as the next digit of our solution. 
Result so far: 18.0
If we take 320 away from 343, we end up with 23.
Append the next digit (2) from the dividend to 23 and continue with: 232 / 40

Let's proceed to step 4:
When dividing 232 by 40, we get 5 with a remainder of 32.
The number 5 becomes the next digit in our result. 
Result so far: 185.0
Deduct 200 from 232 and we're left with 32.
Take the next digit (0) from the dividend and append it to 32, then repeat: 320 / 40

Step 5:
When dividing 320 by 40, we get 8 with a remainder of 0.
Write down 8 as next digit of the result. 
Result so far: 1858.0
Deduct 320 from 320 and we're left with 0.
Include the next digit (9) from the dividend after 0, then repeat: 9 / 40

Let's proceed to step 6:
40 goes into 9 0 times with a remainder of 9.
The next digit of our result is 0. 
Result so far: 18580.0
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.

Step 7:
If we divide 90 by 40, we get 2 and a remainder of 10.
The number 2 becomes the next digit in our result. 
Result so far: 18580.2
Subtract 80 from 90 to get 10.
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 8:
If we divide 100 by 40, we get 2 and a remainder of 20.
Record the quotient 2 as the next digit in the result. 
Result so far: 18580.22
Subtracting 80 from 100 leaves us with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

The final outcome is 18580.22, with a leftover of 0.02.