Introductory Statistics 9th Edition

Area to the left of the x value = .05 From Table IV, this value of z is $z= -1.645$. Thus, it follows: x = μ+zσ = 15+(-1.645)(2.4) = 11.052 minutes
Area to the left of the x value = .05 From Table IV, this value of z is $z= -1.645$. Thus, it follows: x = μ+zσ = 15+(-1.645)(2.4) = 11.052 minutes