Do the following summarize a categorical variable or a numerical variable? Explain.
(1) For a football player, the average number of yards per carry in one game
(2) For a basketball player, the shooting percentage during one game
(3) For a baseball player, his batting average during the playoffs
(4) For a hockey player, the time on ice per game
Researchers carried out a survey of fourth-, fifth-, and sixth-grade students in Michigan. Students were asked whether good grades, athletic ability, or being popular was most important to them. This two-way table summarizes the survey data.
Suppose we select one of these students at random. What's the probability that: The student is a sixth grader or a student who rated good grades as important?