Question

Suppose a jar contains 8 red marbles and 10 blue marbles. If you reach in the jar and pull out 2 marbles at random, find the probability that both are red. Write your answer as a reduced fraction.

Answer 1

Answer: There is a 28/153 chance of both marbles you pull being red.

Step-by-step explanation: So you have 18 marbles total and 8 of them are red, so there is initially an 8/18 or 4/9 chance of pulling the first red marble. After this there is 1 less red marble in the jar so 7 out of 17 marbles are red. Now you have to multiply the fractions 4/9 and 7/17, which gives you 28/153