A national car insurance company stated that in 1987, the average yearly car insurance cost for a family in the U.S. was $931. In the same year, a random sample of 39 families in california resulted in a mean cost of X = $975 with a standard deviation of = 30.50. Does this suggest that the average insurance cost for a family in california in 1987 exceeded the national average? Perform the hypothesis test at a significance level of 5%.© BrainMass Inc. brainmass.com March 4, 2021, 5:51 pm ad1c9bdddf
Null Hypothesis:Ho:M =931
Alternative Hypothesis:H1: M >= 931
Mean=M = 931
Standard deviation =s= 30.50
sample size=n= 39
sx=standard error of mean=s/square ...
The solution tests the hypothesis that the average insurance cost for a family in california in 1987 exceeded the national average.