Suppose a jar contains 14 red marbles and 39 blue marbles. If you reach in the jar and pull out 2 marbles at random at the same time, find the probability that both are red.

Question

Suppose a jar contains 14 red marbles and 39 blue marbles. If you reach in the jar and pull out 2 marbles at random at the same time, find the probability that both are red.

Answer 1

what's the probability that one of the marbles you grab is red:

14/(14+39)=14/53

now whats the probability of doing it again but with one less red marbel:

13/(13+39)=13/52

multiply these probabilities together to get your answer:

(14/53)*(13/52)=.066=6.6%