Question 214850
There is a .45 probability that John will purchase a new car, a .35 probability that Mary will purchase a new car, and a .20 probability they both will purchase a new car.  What is the probability that:

a. Mary or John will purchase a new car
P(M or J) = P(M) + P(J) - P(M and J)
P(M or J) = 0.35 + 0.45 - 0.20 = 0.60
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b. Neither Mary or John will purchase a new car
P(neither) = 1 - P(M or J) = 1-0.60 = 0.40
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Cheers,
Stan H.