The manager of a grocery store wants to determine whether the amount of water contained in a 1L bottle purchased from a known manufacturer actually averages to 1L. It is known from the manufacturer's specifications that the standard deviation of the amount of water is equal to 0.02L. A random sample of 32 bottles is selected, and the mean amount of water per 1L bottle is found to be 0.995L.
-The test statistic is _____.
A)-2.83
B)-1.41
C)-2.00
D)2.83
E)1.41

Question

Quizplus · Accepted Answer

To find the test statistic, we first need to calculate the sample mean and standard deviation. Sample mean = (103+97+104+96+98)/5 = 99.6. Sample standard deviation = sqrt([(103-99.6)^2 + (97-99.6)^2 + (104-99.6)^2 + (96-99.6)^2 +(98-99.6)^2]/(5-1)) = 2.4083. The test statistic is equal to (sample mean - hypothesized value) / (sample standard deviation / sqrt(sample size)) = (99.6-100)/(2.4083/sqrt(5)) = -1.41. Therefore, the best choice is B, -1.41 as the test statistic.

The Manager of a Grocery Store Wants to Determine Whether