A recent article in USA Today discussed prices for the 200 brand-name drugs most commonly used by Americans over age 50. Atrovent, a treatment for lung conditions such as emphysema, was one of the drugs. The file titled Drug$ contains daily cost data similar to those obtained in the research.
a. Produce a relative frequency histogram for these data. Does it seem plausible the data were sampled from a population that was normally distributed?
b. Compute the mean and standard deviation for the sample data in the file Drug$.
c. Assuming the sample came from a normally distributed population and the sample standard deviation is a good approximation for the population standard deviation, determine the probability that a randomly chosen transaction would yield a price of $2.12 or smaller even though the population mean was $2.51.