Camping: Cost of a Sleeping Bag How much does a sleeping bag cost? Let’s say you want a sleeping bag that should keep you warm in temperatures from 20F to 45F. A random sample of prices ($) for sleeping bags in this temperature range was taken from Backpacker Magazine: Gear Guide (Vol. 25, Issue 157, No. 2). Brand names include American Camper, Cabela’s, Camp 7, Caribou, Cascade, and Coleman.

80 90 100 120 75 37 30 23 100 110 105 95 105 60 110 120 95 90 60 70

(a) Use a calculator with mean and sample standard deviation keys to verify that x < $83.75 and s < $28.97.

(b) Using the given data as representative of the population of prices of all summer sleeping bags, fi nd a 90% confi dence interval for the mean price m of all summer sleeping bags.

(c) Interpretation What does the confi dence interval mean in the context of this problem?