An automobile manufacturer has given its car a 53.7 miles per gallon (MPG) rating. An independent testing firm has been contracted to test the actual MPG for this car since it is believed that the car performs under the manufacturer's MPG rating. After testing 200 cars, they found a mean MPG of 53.4. Assume the population variance is known to be 2.25. Is there sufficient evidence at the 0.02 level to support the testing firm's claim? State the null and alternative hypotheses. Find the value of the test statistic. Round your answer to two decimal places. Specify if the test is one-tailed or two-tailed. Find the p-value of the test statistic. Round your answer to four decimal places. Identify the level of significance for the hypothesis test. Make the decision to reject or fail to reject the null hypothesis.
Added by Elizabeth R.
Step 1
State the null and alternative hypotheses: You are correct. The null hypothesis (H0) is that the mean MPG is equal to the manufacturer's rating, and the alternative hypothesis (Ha) is that the mean MPG is less than the manufacturer's rating. H0: μ = 53.7 Ha: μ < Show more…
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