In a study of how the environment affects spending, researchers varied the presence of music and scents in a shopping mall. Interviews with shoppers who made unplanned purchases revealed the following average purchase amounts. Each group has about 100 shoppers.18
Condition Mean Spending ($)
None.......... 64.00
Scent.......... 55.34
Music......... 96.89
Scent and music..... 36.70
(a) If each group includes 100 shoppers, which group spent the most money in toto?
(b) If medians summarized each group’s spending rather than means, would you be able to identify the group with the largest spending?
(c) Did every shopper who was exposed to scent and music spend less than every shopper who was only exposed to music?