12.26The march 14,2009, Boston Globe article "bargains on the menu-and a Side of Jitters" reported concerns that Resonant Week would not be well attended due to the economy this year. Local restaurants were coming up with special promotions to draw past and new customers. Keeping this in mind, a waitress wondered if the "reduced" prices would also "reduce" tip percentages-especially on the lower-cost promotions and midweek shifts. To test her hypothesis, she collected the following data.
Percent Tip
Amount of Bill Tuesday Thursday Saturday
($0- $29) 21 15 12
19 17 18
15 18 19
19 14 13
($30- $59 ) 17 1 10
16 16 14
22 18 22
18 12 17
($60- $89) 20 21 31
14 19 25
15 16 24
24 15 30
A. At the 0.05 level of significance, does the data provide sufficient reason to support that the day of the week had an effect on the percent tip received?
B. At the 0.05 level of significance, does that date provide sufficient reason to support that the amount of the bill had an effect on the percent tip received?