A marble shop contains 5 blue marbles, 5 red marbles, and 5 green marbles. If 2 marbles are purchased at random from the shop, what is the probability that the 2 marbles will be of the red?  Choose the most appropriate option
A) 5/15
B) 2/21
C) 20/15
D) 5/210
E) 4/14
Of the 15 marbles we are wanting red:   Probability of choosing 1st red marble: 5/15   Probability of Choosing 2nd red marble: 4/14   Multiply and you get 20/210 simplified to 2/21   Answer 2/21.
<result>B</result>
A marble shop contains 5 blue marbles, 5 red marbles, and 5 green marbles. If 2 marbles are purchased at random from the shop, what is the probability that the 2 marbles will be of the red?