Question

# In a randomized​ double-blind, placebo-controlled trial of​ children, an herb was tested as a treatment for...

In a randomized​ double-blind, placebo-controlled trial of​ children, an herb was tested as a treatment for upper respiratory infections in children.​ "Days of​ fever" was one criterion used to measure effects. Among 320 children treated with the​ herb, the mean number of days with fever was 0.81 with a standard deviation of 1.42 days. Among 372 children given a​ placebo, the mean number of days with fever was 0.62 with a standard deviation of 1.15 days. Use a 0.05 significance level to test the claim that the herb affects the number of days with fever. Based on these​ results, does the herb appear to be​ effective? Assume that the two samples are independent simple random samples selected from normally distributed​ populations, and do not assume that the population standard deviations are equal. Let population 1 be children treated with the herb.

What are the null and alternative hypotheses for the hypothesis​ test?

Identify the test statistic:

Identify the P Value:

What is the conclusion based on the hypothesis​ test?

The​ P-value is (less than, greater than) the significance level of α=0.05​, so (reject, fail to reject) the null hypothesis. There (is, is not) sufficient evidence to support the claim that the fatality rate is higher for those not wearing seat belts.