Question

marketing researcher wants to estimate the mean savings​ ($) realized by shoppers who showroom. Showrooming is the practice of inspecting products in retail stores and then purchasing the products online at a lower price. A random sample of 81 shoppers who recently purchased a consumer electronics item online after making a visit to a retail store yielded a mean savings of $53 and a standard deviation of $49.

a. Construct a 90 % confidence interval estimate for the mean savings for all showroomers who purchased a consumer electronics item.

Answer 1

sample mean = 53

sample sd = 49

n = 80

t value for 90% = TINV( 0.1, 80) = 1.664

CI = mean + /- E

CI = 53 +/ - 9.0602

CI = (43.9398 , 62.0602 )

ANS: CI = (43.94 , 62.06)