45 of all tourists who visit NYC go to the Empire State Buil

45% of all tourists who visit NYC go to the Empire State Building. 55% go to the Statue of Liberty. 20% go to both the Empire State Building and the Statue of Liberty. What is the probability that a randomly chosen tourist visits the Empire state Building or the Statue of Liberty?

Solution

Prob that a randomly chosen tourist visits the Empire state Building = 45% = 0.45

Prob that that a randomly chosen tourist visits the Statue of Liberty = 55% = 0.55

Prob that a person goes to both = 0.20

Hence prob that a randomly chosen tourist visits the Empire state Building or the Statue of Liberty

= 0.45+0.55-0.20

= 0.80