Question

Previously, an organization reported that teenagers spent an average of 4.3 hours per week, on average, on the phone. The organization thinks that, currently, the mean is higher. Fifteen randomly chosen teenagers were asked how many hours per week they spend on the phone. The sample mean was 5.75 hours with a sample standard deviation of 2.0. What are the null and alternate hypotheses

Answer 1

The null hypothesis is
`H_(0) = 4.3`.

The alternate hypothesis is
`H_(a) > 4.3`

Explanation:

Null hypothesis:

The previously report, the known value.

Alternate hypothesis:

What is questioned(higher, lower, different,...) of the null hypothesis

Previously, an organization reported that teenagers spent an average of 4.3 hours per week, on average, on the phone.

This means that the null hypothesis is
`H_(0) = 4.3`.

The organization thinks that, currently, the mean is higher.

That is, higher than 4.3. So

The alternate hypothesis is
`H_(a) > 4.3`