A bag holds 8 yellow marbles and 5 orange marbles.How many and what color marbles would you add to the bag so that the probability of picking a yellow marble is 2/3

Answer 1

Since there are 5 orange, and that makes up 1/3 of the total bag, you would multiply that by 3 to get the total amount. 2/3 of that is 10 marbles. Since there are currently 8, you subtract 8 from 10, giving you 2 marbles