I believe the answer is 17.
Answer:
0.6170
Step-by-step explanation:
Given that a manufacturing process is designed to produce bolts with a 0.25-in. diameter.
i.e. no of bolts which are produced as per standard is X means then
X is normal with mean = 0.250 and std dev = 0.04
No of bolts tested = 36
If this mean falls outside the interval (0.230,0.270) the production would be shut down.
i.e. P(|x-25|>0.20) =production shut down probability

We can set up a proportion to find this
60 x
--- = ----
100 1200
then we cross multiply and divide to solve
60 times 1200 is 72000 divided by 100 is 720
now we know his employer pays 720 out of 1200
we subtract to find out how much he pays
1200-720 is 480
fred pays 480