EXERCISES

4. Box I contains 3 red and marbles while Box II contains 2 red and 8 blue.

- If a single marble is selected at random from either box, find the probability that:

a) both are blue

b) one is red and one is blue

- A fair coin is tossed. If the coin turn up heads and a marble is chosen from Box I; if turns up tails marble is

chosen from Box II. Find the probability that:

c) a red marble is chosen

d) Box I is chosen (the coin turned up head), given a red marble has chosen.