Cars are either race-car fast, slightly fast, or normal. It turns out that 10% of all cars are race-car fast, 40% are sligh
tly fast, and 5% are normal. Of those that are race-car fast 70% are red, as are 45% of those that are slightly fast, and 30% of those that are normal. what is the probability that a randomly selected car is red given that it is normal?
Prob (Red Car) = 70% of race fast cars, & 45% of slight fast cars, & 30% of Normal cars, & = (70% x 10%) + (45% x 40%) + (30% x 50%) = 7% + 18% + 15% = 40%
Prob (Normal & Red Car) = 30% of 50% = 15%
Prob (Red car I Normal car) = Prob (Red & Normal Car I Normal Car) = 15% / 40% = 37.5%
