Question

Commuting ~ According to 2016 U.S. Census, the average commuting time of Michiganders is 24.4 minutes. A random sample of 120 Michigan workers has a mean commuting time of 23.08 minutes and a standard deviation of 8.3 minutes.

Note: Numbers are randomized in each instance of this question. Pay attention to the numbers in this question.

A researcher wonders if the actual mean commuting time of Michiganders is less than the value reported in the 2016 Census.

What is the p-value for this hypothesis test? Give your answer to 4 decimal places.

Your Answer:

Answer 1

Solution :

This is the left tailed test .

The null and alternative hypothesis is ,

H0 :   =24.4

Ha : <24.4

Test statistic = z

= ( - ) / / n

= (23.08-24.4) / 8.3/ 120

Test statistic = -1.74

P(z <-1.74 ) = 0.0409 using z table

P-value = 0.0409