Question

A bag contains 2 red marbles, 3 green marbles, and 5 blue marbles. Elizabeth draws a marble from the bag, replaces the marble, and draws another marble. What is the probability she draws 2 red marbles?

Answer 1

2 red, 3 green, 5 blue....total of 10 marbles
P(1st one is red) = 2/10 which reduces to 1/5
replaces the marble
P(2nd one is red) = 2/10 which reduces to 1/5

P(both red) = 1/5 * 1/5 = 1/25