Question

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 1.21 cups per day and 1.40 for those drinking decaffeinated coffee. A random sample of 54 regular coffee drinkers showed a mean of 4.59 cups per day. A sample of 49 decaffeinated coffee drinkers showed a mean of 5.64 cups per day.

a) Is this a One-tailed or Two-tailed test?

b) State the decision rule

c) Compute the value test statistic

d) What is the p-value

e) What is the decision (reject or do not reject)

Answer 1

Here, level of significance alpha is not given so, we can use alpha = 0.05

## one tailed test.

## p-value = 0

## reject the null hypothesis.