Question

Aly is looking for a new car. She has test-driven two cars but can only purchase one. The probability that she will purchase car A is 0.47 and the probability that she will purchase car B is 0.35. What is the probability that she will not purchase either car A or car B? 0.12 0.41 0.82 0.18

Answer 1

The probability of buying A or B is P(A∪B) = 0.47 + 0.35

P(A∪B) = 0.82
But the probability of NOT buying either is :
 P(A'∪B') = 1 - 0.82 = 0.18

Answer 2

P(A) = 0.47
P(B) = 0.35
The probability of an event occurring ranges from 0 to 1, or 0 to 100%.
P(not A or not B) would be the complement of the events occurring.
The probability of an event and its complement is always 1.
Ex.  P(A) + P(A') = 1
P(A) + P(B) = 0.47 + .35 = 0.82
P(not A or not B) = 1 - 0.82 = 0.18
Last option