a. Data Set 9 in Appendix B includes a sample of 35 movies, and 12 of them have ratings of R. What percentage of these 35 movies have R ratings?

b. In a study of 4544 students in grades 5 through 8, it was found that 18% had tried smoking (based on data from “Relation between Parental Restrictions on Movies and Adolescent Use of Tobacco and Alcohol,” by Dalton et al., Effective Clinical Practice, Vol. 5, No. 1). How many of the 4544 students tried smoking?