It is known that 20% of all students in some large university are overweight, 20% exercise regularly and 2% are overweight and exercise regularly.What is the probability that a randomly selected student is either overweight or exercises regularly or both?
A)0.40
B)0.38
C)0.20
D)0.42
E)0.10

Question

Quizplus · Accepted Answer

To find the probability that a student is either overweight or exercises regularly or both, we use the formula for the union of two events: P(A or B) = P(A) + P(B) - P(A and B). Here, P(A) = 0.20 (overweight), P(B) = 0.20 (exercises regularly), and P(A and B) = 0.02 (overweight and exercises regularly). So, P(A or B) = 0.20 + 0.20 - 0.02 = 0.38.

It Is Known That 20% of All Students in Some