Question

State the null and alternative hypotheses?

Short answer

The null hypothesis is $H_0:{\sigma }^2=0.{81}^2$.

The alternative hypothesis is $H_a:{\sigma }^2>0.{81}^2$.

Step-by-step solution

Given Information

The standard deviation of heights for students in a school is $0.81$.

A researcher in charge of the study believes the standard deviation of heights for the school is greater than $0.81$.

Explanation

The standard deviation of heights for students in a school is $0.81$. Therefore, the null hypothesis is $H_0:{\sigma }^2=0.{81}^2$.

A researcher in charge of the study believes the standard deviation of heights for the school is greater than $0.81$.

Therefore, the alternative hypothesis is$H_a:{\sigma }^2>0.{81}^2$.