Question

For a certain class, the following data table summarizes the amount of sleep of students and whether or not they have an A in the class. What is the probability that a student chosen randomly from the class has an A?
Slept more than 6 hours Slept 6 hours or less
Has an A 10 5
Does not have an A 2 9

Answer 1

There are 10 + 5 = 15 students with an A, out of a total of 10 + 5 + 2 + 9 = 26 students.

Probability = 15/26 ≈ 0.5769 (about 57.7%).