Question

A bag contains 5 blue marbles 6 red marbles and 9 green marbles two marbles are drawn at random one at a time and without replacement what is the probability of selecting two red marbles

Answer 1

Answer:3/38

Explanation:

Answer 2

Sample space={5 B + 6 R + 9 G} = 20 (all possible outcomes
Favorable outcome ={6 R} = 6

P(1st Drawing R) = 6/20 = 3/10
Once drawn and not replaced the total remaining marble = 19 and within the 19, there are 5 Red left. So
P(2nd Drawing R) = 5/19

P( 1st AND 2nd R) = (3/10)x(5/19) = 3/38 = 0.0789