Eva has 3 red and 4 blue beads in her pocket. She randomly selects 2 beads. What is the probability that both of them are red?

12/ 26 =0.46

Step-by-step explanation:

This question is most simply solved with a probability tree diagram, where you just follow the paths of picking two same coloured beads. The first branch would be picking two red beads. P(R1) = 3 / 7, and P(R2) = 2 / 6, as the red bead would have been removed. The second branch would be picking two blue beads, where P(B1) = 4 / 7 and P(B2) = 3 / 6 for the same reason.

Our total probability is then (R1 x R2) + (B1 x B2) = (3 / 7x 2 / 6) + (4 / 7  x 3 / 6) = 12/ 26