Question

An urban planner is researching commute times in the San Francisco Bay Area to find out if commute times have increased. In which of the following situations could the urban planner use a hypothesis test for a population mean? Check all that apply. Group of answer choices The urban planner asks a simple random sample of 110 commuters in the San Francisco Bay Area if they believe their commute time has increased in the past year. The urban planner will compute the proportion of commuters who believe their commute time has increased in the past year. The urban planner collects travel times from a random sample of 125 commuters in the San Francisco Bay Area. A traffic study from last year claimed that the average commute time in the San Francisco Bay Area is 45 minutes. The urban planner will see if there is evidence the average commute time is greater than 45 minutes. The urban planner asks a random sample of 100 commuters in the San Francisco Bay Area to record travel times on a Tuesday morning. One year later, the urban planner asks the same 100 commuters to record travel times on a Tuesday morning. The urban planner will see if the difference in commute times shows an increase.

Answer 1

Explanation:

The required hypothesis test is that for a single population mean. It wouldn't involve population proportion or difference between two population means. The correct answer choice would be

A traffic study from last year claimed that the average commute time in the San Francisco Bay Area is 45 minutes. The urban planner will see if there is evidence the average commute time is greater than 45 minutes.

Answer 2

Explanation:

The urban planner collects travel times from a random sample of 125 commuters in the San Francisco Bay Area. A traffic Study from last year claimed that the average commute time in the San Francisco Bay Area is 45 min. The urban planner will see if there is evidence the average commute time is greater than 45 minutes

( Here in this case, Null hypothesis will be Η :μ = 45

And the Alternate Hypoyhesis will be H, :μ> 45 )

C. The urban planner asks a random Sample of 100 commuters in the San Francisco Bay Area to record travel times on a Tuesday morning. One year later, the urban planner asks the same 100 commuters to record travel times on a tuesday morning . The urban planner will see the difference in commute time shows an increase.

Here in this case the null hypothesis will be, H₀ :
`\mu _d` = 0

And the Alternate Hypothesis will be H, :
`\mu _d` <0 The commute time after 1 year is more