Question

One of the important factors in auto safety is the weight of the vehicle. Insurance companies are interested in knowing the average weight of cars currently licensed in the United States; they believe it is 3000 pounds. To see if that estimate is correct, they checked a random sample of 91 cars. For that group, the mean weight was 2919 pounds, with a standard deviation of 531.5 pounds. Is this strong evidence that the mean weight of all cars is not 3000 pounds? What best describes the p-value and what tail of the t distribution that the p-value lies in? a. p-value=0.1494 This p-value lies in the lower tail of the t distribution. b. p-value=0.1494 This p-value lies in the upper tail of the t distribution. c. p-value=0.1494 Half the p-value lies in the lower tail and half the p-value lies in the upper tail of the t distribution. d. Both answers a and c. Select the best interpretation of the p-value. 14.94% of the time we would have seen data like the data we got in our sample, if Ha was true. 14.94% of the time we would have seen data like the data we got in our sample, if Ho was true. I'm 95% confident that the population mean is within 14.94% of our sample mean. I'm 95% confident that the population mean is within 14.94% of 3000. One of the important factors in auto safety is the weight of the vehicle. Insurance companies are interested in knowing the average weight of cars currently licensed in the United States; they believe it is 3000 pounds. To see if that estimate is correct, they checked a random sample of 91 cars. For that group, the mean weight was 2919 pounds, with a standard deviation of 531.5 pounds. Is this strong evidence that the mean weight of all cars is not 3000 pounds? Select the best statistical decision. Accept Ho. Fail to Reject Ho. Reject Ho. Reject Ha. Accept Ha. Fail to Reject Ha. Select the best conclusion. There is enough evidence that the population mean weight of cars is not equal to 3000. There is not enough evidence that the population mean weight of cars is not equal to 2919. There is enough evidence that the population mean weight of cars is not equal to 2919. There is not enough evidence that the population mean weight of cars is not equal to 3000.

Answer 1

------------------------------------------------

c. p-value=0.1494 Half the p-value lies in the lower tail and half the p-value lies in the upper tail of the t distribution.

14.94% of the time we would have seen data like the data we got in our sample, if Ho was true.

Fail to Reject Ho.

There is not enough evidence that the population mean weight of cars is not equal to 3000.