Rhino viruses typically cause common colds. In a testof the effectiveness of echinacea, 40 of the 45 subjects treated with echinacea developed rhinovirus infections. In a placebo group, 88 of the 103 subjects developed rhinovirus infections(based on data from "An Evaluation of Echinacea Angustifolia in Experimental RhinovirusInfections," by Turner, et al., New England Journal of Medicine, Vol. 353, No. 4). We wantto use a 0.05 significance level to test the claim that echinacea has an effect on rhinovirusinfections.

Given,

H₀: p1 =p2

H₁: p1 p2

Find, Test Statistic (z) = (Round to 2 decimals)

Critical Value (z) = (Round to 2 decimals)

P-Value = (Round to 4 decimals)

Decision about H₀(Reject or Fail to Reject):

Conclusion (Sufficient or Not Sufficient):

Confidence Interval: < p1-p2 < (Round to 4 decimals)