Question

a bag contains four red marbles and seven blue marbles. you randomly pick a marble and then pick a second marble without returning the marbles to the bag. what is the probability that both marbles are red.

Answer 1

6/55

Explanation:

4 red + 7 blue = 11 marbles in total

P(first red) = 4/11.

we now have 10 marbles left. 3 of them are red.

P(second red) = 3/10

P(both red) = 4/11 X 3/10 = 12/110 = 6/55