Tell whether each situation is a combination problem or a permutation problem. There are 100 comic books to choose from at the local hobby store. How many different sets
of 10 comic books could you choose to buy?

Permutation
Combination

Arandom sample of n = 25 observations is taken from a n(µ, σ ) population. a 95% confidence interval for µ was calculated to be (42.16, 57.84). the researcher feels that this interval is too wide. you want to reduce the interval to a width at most 12 units. a) for a confidence level of 95%, calculate the smallest sample size needed. b) for a sample size fixed at n = 25, calculate the largest confidence level 100(1 − α)% needed.