Problem
Big babies: The National Health Statistics Reports described a study in which a sample of 310 one-year-old baby boys were weighed. Their mean weight was 24.4 pounds with standard deviation 5.3 pounds. A pediatrician claims that the mean weight of one-year-old boys is less than 25 pounds. Do the data provide convincing evidence that the pediatrician's claim is true? Use the $\alpha=0.10$ level of significance and the critical value method with the Critical Values for the Student's $t$ Distribution Table. Part: 0 / 5 Part 1 of 5 (a) State the appropriate null and alternate hypotheses. \[ \begin{array}{l} H_{0}: \square \\ H_{1}: \square \end{array} \] This hypothesis test is a (Choose one) $\mathbf{\nabla}$ test.
Solution
Step 1 ：State the appropriate null and alternate hypotheses. The null hypothesis \(H_{0}: \mu = 25\) states that the mean weight of one-year-old boys is 25 pounds. The alternate hypothesis \(H_{1}: \mu < 25\) states that the mean weight of one-year-old boys is less than 25 pounds.
Step 2 ：This hypothesis test is a one-tailed test because we are testing if the mean weight is less than a certain value.
