State the null hypothesis and the alternate hypothesis
Information from AAA indicates that the mean age of passenger cars in the US is 8.4 years. A sample of 40 cars in the student lots at the local university showed the mean age to be 9.2 years. The standard deviation of this sample was 2.8 years. At the 0.01 significance level can we conclude the mean age is more than 8.4 years for cars of university students?
i. State the null hypothesis and the alternate hypothesis.
ii. What is the p-value?
iii. What is the critical value of test statistic?