Answer to Question #21240 in Statistics and Probability for francisco maella

Question

a cannery claims that its sardine cans have a net weight of 8 oz, with a standard deviation of 0.1 oz. you take a simple random sample of 30 cans and ecounter a sample mean of 7.85 oz. Are you inclined to believe the claim?

E(X) = 8
SE(X) = standev/sqrt(n) = .1/sqrt(30) = 0.0183

the solution then says that P(X<7.8) = P(Z<-8.2) = 0, thus the cannery is not telling the truth

my question is an explation on how we get from SE(X) to the P(X<7.8) = P(Z<-8.2)