Answer:

And the best option would be:

Step-by-step explanation:
We assume that the distribution for the random variable is:

For this case we want to calculate the following probability:

And we can use the normal standard distribution or excel and we got:

And the best option would be:

We can convert 7/10 to a decimal first.
7/10 = 0.7
Now we can multiply this problem easier.
35 x 0.7 = 24.5
306 / 18 = 17
So he's on $17 / hour
$204 / $17 = 12.
Therefore he'd make $204 in 12 hours.