Answer:
90% confidence interval for the true average number of alcoholic drinks all UF "non-greek" students have in a one week period is between a lower limit of 3.24 and an upper limit of 4.08.
Explanation:
Confidence interval is given as mean +/- margin of error (E)
mean = 3.66
sd = 2.82
n = 124
degree of freedom = n-1 = 124-1 = 123
confidence interval = 90%
Significance level = 100 - 90 = 10%
Critical value (t) corresponding to 123 degrees of freedom and 10% significance level is 1.6577
E = t×sd/√n = 1.6577×2.82/√124 = 0.42
Lower limit = mean - E = 3.66 - 0.42 = 3.24
Upper limit = mean + E = 3.66 + 0.42 = 4.08
90% confidence interval is (3.24, 4.08)
