When 100 randomly selected car owners are surveyed,it is found that the mean length of time they plan to keep their car is 7.01 years,and the standard deviation is 3.74 years.Calculate the appropriate test statistic to test the claim that the mean for all car owners is less than 7.5 years.
A)-13.10
B)-2.53
C)-1.31
D)1.31
E)2.53

Question

Quizplus · Accepted Answer

The test statistic is calculated using the formula: (sample mean - population mean) / (standard deviation / sqrt(sample size)). Here, it is (7.01 - 7.5) / (3.74 / sqrt(100)) = -1.31.

When 100 Randomly Selected Car Owners Are Surveyed,it Is Found