Hypothesis test

Formulate the null and alternative hypothesis in each case:

a.

An e-commerce research company claims that 60% or more graduate students have bought merchandise on-line. A consumer group is suspicious of the claim and thinks that the proportion is lower than 60%.

b.

The administrator at your local hospital states that on weekends the average wait time for emergency room visits is 10 minutes.Based on discussions you have had with friends who have complained how long they waited to be seen over the weekend, you dispute the administrator's claim.

c.

An inventor has developed a new, energy-efficient lawn mower engine. He claims that the engine will run continuously for 300 minutes on a single gallon of regular gasoline. However, you think the engine will not run for 300 minutes on a single gallon.

d.

The principal of a school thinks that the average IQ of students is 110.20students were randomly selected and among the sampled students, the average IQ is 108.You suspect the claim is lower than 110.

e.

We want to show that children on average have higher cholesterol levels than the national average.It is known that the mean cholesterol level for all Americans is 190.