Drawing Marbles

A jar contains 5 red, 2 blue, and 3 green marbles.   A marble is chosen at random and then replaced back into the jar.   What is the probability that Wendy will draw a pair of matching marbles in two consecutive draws?

A jar contains 2 red, 3 blue, and 4 green marbles. Bill draws one marble from the jar, and then Tom draws a marble. What is the probability that Bill will draw a green marble and Tom will draw a blue marble?

A box has red, blue, and green marbles.   There is a 1/3 probability that a red will be drawn, a 2/5 probability that a blue will be drawn, and a ¼ probability that a green marble will be drawn.   What is the fewest number of marbles in the box?

Related InterMath Investigation
Adding Marbles