What is the probability that a car chosen at random is red?

Question

A used car dealer sells SUVs and cars. Of all the vehicles, 70% are cars. Of all the vehicles, 20% are red cars. Round your answer to the nearest tenth of a percent.

Answer 1

if you draw a tree, the upper branch labeled car has probability 0.7;

the subsequent branch emanating from that is labeled RED and it has probability p.

Then the probability of both of these events is 0.7p = 0.2

Thus P(RED car) = 2.7