Q3: An electrical store provides 65% of lamps from producer A and 35% from producer B. Suppose that 2% of the products of producer A and 4% of the products of producer B are defective.

a) Make a tree diagram and indicate the events and their probabilities on it.

b) Calculate the probability that a randomly selected lamp in the store is defective?

Use 3 decimal places.

c) If a defective lamp is found in the store, what is the probability that it is produced

by producer A? Use 3 decimal places.