Shopping. A survey of 430 randomly chosen adults found that 21% of the 222 men and 18% of the 208 women had purchased books online.
a) Is there evidence that men are more likely than women to make online purchases of books? Test an appropriate hypothesis and state your conclusion in context.
b) If your conclusion in fact proves to be wrong, did you make a Type I or Type II error?
c) Estimate this difference with a confidence interval.
d) Interpret your interval in context.