Question

Suppose you choose a marble from a bag containing 3 red marbles, 5 white marbles, and 4 blue marbles. You return the first marble to the bag and then choose again. Find P(red and blue).

Answer 1

This is "with replacement", so the events are independent, so the final probability will be a product. Hint: you could have red and then blue or blue and then red.

Answer 2

Start with your first pick and only your first pick for now. What is the P(red)?

Answer 3

How many total marbles in the bag before any pick?