A coffee manufacturer is interested in whether the mean daily consumption of regular-coffee drinkers is less than that of decaffeinated-coffee drinkers. Assume the population standard deviation for those drinking regular coffee is 1.35 cups per day and 1.49 cups per day for those drinking decaffeinated coffee. A random sample of 49 regular-coffee drinkers showed a mean of 4.20 cups per day. A sample of 45 decaffeinated-coffee drinkers showed a mean of 5.10 cups per day.
Use the 0.050 significance level.
a-) Is this a one-tailed or a two-tailed test?
One-tailed test.
Two-tailed test.
State the decision rule. (Negative amount should be indicated by a minus sign. Round your answer to 2 decimal places.)
The decision rule is to reject Ho. μRegular ≥ μDecaf if z < ___________
c- Compute the value of the test statistic. (Negative amount should be indicated by a minus sign. Round your answer to 2 decimal places.)
Value of the test statistic _____________
d- What is the p-value?
The p-value is ___________
e- What is your decision regarding H_{0}?
( ) Reject H_{0}.
( ) Do not reject H_{0}.
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