LUKE HAS RED MARBLES AND BLUE MARBLES IN A BAG. IF HE CHOOSES A MA...

20. Luke has red marbles and blue marbles in a bag. If he chooses a marble at random,

the probability that he will choose a blue marble is

²

₅

. Luke adds 5 blue marbles to

the bag and removes 5 red marbles. If he chooses a marble at random, the probability

that he will choose a blue marble is now

³

₅

. How many marbles are in the bag?

(A) 20 (B) 10 (C) 45 (D) 50 (E) 25

Part C: Each correct answer is worth 8.