The Substance Abuse and Mental Health Services Administration conducts surveys on drug use by type of drug and age group. Results are published in National Household Survey on Drug Abuse. According to that publication, 13.6% of 18- to 25-year-olds were current users of marijuana or hashish in 2000. A recent poll of 1283 randomly selected 18- to 25-year-olds revealed that 205 currently use marijuana or hashish. At the 10% significance level, do the data provide sufficient evidence to conclude that the percentage of 18- to 25-yearolds who currently use marijuana or hashish has changed from the 2000 percentage of 13.6%?
Answer to relevant QuestionsIn 2006, 9.8% of all U.S. families had incomes below the poverty level, as reported by the U.S. Census Bureau in American Community Survey. During that same year, of 400 randomly selected Wyoming families, 25 had incomes ...In the article “Prothrombotic Factors in Children With Stroke or Porencephaly” (Pediatrics Journal, Vol. 116, Issue 2, pp. 447–453), J. Lynch et al. compared differences and similarities in children with arterial ...Repeat parts (b)–(e) of Exercise 11.5 for samples of size 4. (There are five possible samples.) x1 = 30, n1 = 80, x2 = 15, n2 = 20; two-tailed test, α = 0.05; 95% confidence interval a. Determine the sample proportions. b. Decide whether using the two-proportions z-procedures is appropriate. If so, also do parts (c) ...Refer to Exercise 11.89 and determine and interpret a 98% confidence interval for the difference between the rates of major birth defects for babies born to women who have taken folic acid and those born to women who have ...
Post your question