A rental firm has only two distinct types of vehicles: minivans and sedans. Each vehicle runs on exactly one fuel type, either gasoline or electricity.
P(sedan running on electricity) > P(minivan running on gasoline)?
Let the probability of sedan, minivan, electric run and gasoline run be S,M,E and G respectively
S1
The probability that a randomly selected vehicle is either a minivan or runs on gasoline is 2/5.
P(M or G) = P(M) + P(G) - P(M and G)
2/5 = P(M) + P(G) - P(M and G)
Also over all,
P(M or G) = 1 - P(S and E)
P(S and E) = 1-2/5 = 3/5
P(M and G) is also part of the same set, so it has to be less than 3/5, in fact less than 2/5 (=1-3/5).
P(sedan running on electricity) > P(minivan running on gasoline)
Sufficient
(2) The probability that a randomly selected vehicle is either a sedan or runs on electricity is 5/8.
P(S or E) = 5/8
5/8 = P(S) + P(E) - P(S and E)
Also P(M and G) = 1-P(S or E) = 1-5/8 = 3/8
But we don't know P(S and E)
Insufficient
Answer B
Bunuel
A rental firm has only two distinct types of vehicles: minivans and sedans. Each vehicle runs on exactly one fuel type, either gasoline or electricity. If a vehicle is selected at random, is the probability that it is a sedan running on electricity greater than the probability that it is a minivan running on gasoline?
(1) The probability that a randomly selected vehicle is either a minivan or runs on gasoline is 2/5.
(2) The probability that a randomly selected vehicle is either a sedan or runs on electricity is 5/8.