There are 16 junior high students in the Brewster town swimming club. A student is chosen at random to be the club vice president. The probability of choosing a 7th, 8th, or 9th grader is 1. The probability of choosing a 7th grader is 1/2 . Choosing an 8th grader is more likely than choosing a 9th grader. What is the greatest possible number of 9th graders in the club?
