Question

A study by the National Park Service revealed that 50% of the vacationers going to the Rocky Mountain region visit Yellowstone Park, 40% visit the Grand Tetons, and 35% visit both. What is the probability that a vacationer will visit at least one of these magnificent attractions?

Answer 1

55%

Explanation:

To find the probability that a vacationer will visit at least one of the attractions, it is used the following formula, considering the events are not mutually exclusive (this means that one could happen independent to the other)

P(A or B) = p(A) + p(B) – p(A and B).

Let

A = vacationer who visit Yellowstone Park

B = vacationer who visit Grand Tetons

P (A or B) = 0.5+ 0.4 - 0.35

P (A or B) = 0.55

There is 55% that a vacationes will visit at least an attraction.