Miller (2008) examined the energy drink consumption of college undergraduates and found that males use energy drinks significantly more often than females. To further investigate this phenomenon, suppose a researcher selects a random sample of n=36 male undergraduates and a sample of n=25 females. On average, the males reported consuming M=2.45 drink per month and females had an average of M=1.28. Assume that the overall level of consumption for college undergraduates averages population mean=1.85 energy drinks per month, and that the distribution of montly consumption scores is approximately normal with a standard deviation of 1.2.
a) Did this sample of males consume significantly more energy drinks than the overall population average? Use a one-tailed test with a a=.01
b) Did this sample of females consume significantly fewer enery drinks than the overall population average? Use a one-tailed test with a a=.01