A normal population has a mean of 62 and a standard deviation of 12. You select

(a) Probability that the sample mean is Greater than 64 is 0.2033 .

Step-by-step explanation:

We are given that a normal population has a mean of 62 and a standard deviation of 12 and we select a random sample of 25.

Let X bar = sample mean

The z score probability distribution for sample mean is ;

           Z = ~ N(0,1)

where, = population mean = 62

            = population standard deviation = 12

            n = random sample = 25

So, probability that the sample mean is Greater than 64 = P(X bar > 64)

     P(X bar > 64) = P( < ) = P(Z > 0.83) = 1 - P(Z <= 0.83)

                                                             = 1 - 0.79673 = 0.2033 .