In: Statistics and Probability
How much does a sleeping bag cost? Let's say you want a sleeping bag that should keep you warm in temperatures from 20°F to 45°F. A random sample of prices ($) for sleeping bags in this temperature range is given below. Assume that the population of x values has an approximately normal distribution.
75 | 95 | 55 | 105 | 110 | 115 | 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 find the sample mean price x and sample standard deviation s. (Round your answers to two decimal places.)
x = | $ |
s = | $ |
(b) Using the given data as representative of the population of
prices of all summer sleeping bags, find a 90% confidence interval
for the mean price μ of all summer sleeping bags. (Round
your answers to two decimal places.)
lower limit | $ |
upper limit | $ |