Step 1 :Identify the null and alternative hypotheses. The null hypothesis is that the mean hic measurement is equal to 1000, denoted as \(H_{0}: \mu=1000\) hic. The alternative hypothesis is that the mean hic measurement is less than 1000, denoted as \(H_{1}: \mu<1000\) hic.
Step 2 :Calculate the test statistic. This is done by first calculating the sample mean and standard deviation. Then, subtract the population mean (1000 in this case) from the sample mean and divide by the standard deviation divided by the square root of the sample size. The test statistic is \(t=-3.664\) (rounded to three decimal places).
Step 3 :Calculate the P-value using the test statistic and the t-distribution. The P-value is the probability of observing a test statistic as extreme as the one calculated, assuming the null hypothesis is true. The P-value is approximately 0.007.
Step 4 :Make a conclusion based on the P-value. If the P-value is less than the significance level (0.05 in this case), reject the null hypothesis. This suggests that the mean hic measurement is less than 1000, which would suggest that all of the child booster seats meet the specified requirement.
Step 5 :The final conclusion that addresses the original claim is that the results suggest that all of the child booster seats meet the specified requirement. Therefore, \(\boxed{\text{The null and alternative hypotheses are } H_{0}: \mu=1000 \text{ hic and } H_{1}: \mu<1000 \text{ hic. The test statistic is } t=-3.664. \text{ The P-value is approximately 0.007. Since the P-value is less than the significance level of 0.05, we reject the null hypothesis. This suggests that the mean hic measurement is less than 1000, which would suggest that all of the child booster seats meet the specified requirement.}}\)