Question

Heavy children: Are children heavier now than they were in the past? The National Health and Nutrition Examination Survey (NHANES) taken between 1999 and 2002 reported that the mean weight of six-year-old girls in the United States was 49.3 pounds. Another NHANES survey, published in 2008, reported that a sample of 198 six-year-old girls weighed between 2003 and 2006 had an average weight of 50.5 pounds. Assume the population standard deviation is o = 14.4 pounds. Can you conclude that the mean weight of six-year-old girls is higher in 2006 than in 2002? Use the a = 0.10 level of significance and the P-value method with the TI-84 calculator. Part: 0 / 4 Part 1 of 4 State the appropriate null and alternate hypotheses. HO:

Answer 1

Sal! The null and alternative hypothesis is - Hoit 49.3 He: MY 49.3 Test - statistic - بن n = 198 X = 50.5 14.4 Za X-M 50.5-49.3 1.173 = olm 14,4 / 5198 P-value P(Z 1.173) 0.1904 since, P-value is greater than a=0.10. So, we fail to reject the null hypothesis - There is insufficient evidence to conclude that the mean weight of six - year-old girls is higher in 2006 than in 2009 .