A random sample of students were surveyed as to how much non-school screen time
they had each week (for purposes of the survey, screen time was defined as: time
spent online, on social media, watching TV, or playing video games) and if their grade
average was above or below 80.
Screen Time
less than 4 hours
4-8 hours
8-12 hours
more than 12 hours
above below
6
15
9
13
17
17
11
20
How many total students who spend more than 12 hours a week on screens were
surveyed?