In the July 29, 2001 issue of the Journal News (Hamilton, Ohio), Lynn Elber of the Associated Press reported that "while 40 percent of American families own a television set with a V-chip installed to block designated programs with sex and violence, only 17 percent of those parents use the device."2
a. Use the report's results to find an estimate of the probability that a randomly selected American family has used a V-chip to block programs containing sex and violence.
b. According to the report, more than 50 percent of parents have used the TV rating system (TV-14, etc.) to control their children's TV viewing. How does this compare to the percentage using the V-chip?