A bag contains 3 red, 4 blue and 4 green balls. If 2 ballsare picked at random, what is the probability that both are red?
Choices.
A) 2 / 15
B) 2 / 21
C) 3 / 55
D) 3 / 29
E) 4 / 27

Rationale: "p ( both are red ) , = 3 c 211 c 2 = 3 c 211 c 2 = 3 / 55 c"
Answer: C