Question

there are 5 blue marbles and three red marbles in a bag. one marble is drawn and replaecd. what is the probability that both marbles are red?

Answer 1

8 marbles in total.

1st draw: you need it to be red, so the probability of it being red is 3/8
2nd draw: needs to be red again, and the marble was placed back into the bag, so the probability of getting a red is again 3/8

So the probability of getting red on both draws is: 3/8 * 3/ 8 = 9/64