Question

A bag contains ten marbles of equal size and weight. One marble is blue, one marble is white, three are yellow, and five marbles are red. A marble is taken from the bag two times. Each time a marble is taken out, it is not replaced. What is the probability of picking a red marble and picking a red marble?
A) 1/4

B) 2/9

C) 9/10

D) 7/45

Answer 1

Answer:

B) 2/9

Step-by-step explanation:

First, the probability of picking a red marble is 5/10, which is the same as 1/2. This is because there are 5 marbles in the bag that are red out of the 10 total marbles. Then, because we don't replace the marble, there are now 9 total marbles, with 1 blue, 1 white, 3 yellow, and 4 red. Now the probability of picking a red marble is 4/9.

Multiplying these two probabilities together gives you the probability of picking 2 red marbles in a row, which is 1/2 * 4/9 which is equal to 4/18, or 2/9 when simplified.