A box has 1 red marble, 1 blue marble, and 4 green marbles of the same shape and size. Dan draws a marble randomly from the box, replaces it, and then draws another marble randomly.

A. What is the probability of drawing a green marble first? (3 points)

B. What is the probability of drawing a second green marble? (3 points)

C. What is the probability of drawing two green marbles in a row? Show your work and express the probability as a percent. (4 points)

1 answer

A. The probability of drawing a green marble first is 4/6 or 2/3.

B. Since Dan replaced the first marble, the probability of drawing a green marble again is still 4/6 or 2/3.

C. The probability of drawing two green marbles in a row is the product of the probabilities of drawing a green marble first and then drawing another green marble, which is (2/3) x (2/3) = 4/9 or approximately 44.44%.