A random sample of size 34 is to be selected from a population that has a mean ? = 45 and a standard deviation ? of 10.
a) What is the probability that this sample mean will be between 45 and 55? (Give your answer correct to four decimal places.)
b) What is the probability that the sample mean will have a value greater than 50? (Give your answer correct to four decimal places.)
c) What is the probability that the sample mean will be within 2 units of the mean? (Give your answer correct to four decimal places.)