Cash withdrawals (in multiples of $20) at an on-campus ATM for a random sample of 30 Fridays and 30 Mondays are shown following. At α = .01, is there a difference in the mean ATM withdrawal on Monday and Friday? (a) Make stacked dot plots of the data (a sketch is OK). (b) State the hypotheses. (c) State the decision rule and sketch it. (d) Find the test statistic. (e) Make a decision. (f ) Find the p-value and interpret it.
Friday - 250,20,110,40,70,20,10,50,100,20,10,10,20,20,10,20,20,20,20,60,10,30,10,40,10,400,10,10,20,70
Monday - 40,100,20,30,200,20,10,30,50,60,30,70,20,50,20,30,20,40,10,10,10,370,10,30,40,20,100,20,20,20,