A bag contains 5 green and 8 white balls. If two balls are drawn simultaneously, the probability that both are of the same colour is  Answers.
A) 8 / 15 B) 2 / 5 C) 3 / 5 D) 11 / 15 E) 19 / 39

Rationale: "drawing two balls of same color from five green balls can be done in 5 c ₂ ways . similarly from eight white balls two can be drawn in ⁸ c ₂ ways . p = 5 c ₂ / ¹ ⁵ c ₂ + ⁸ c ₂ / ¹ ⁵ c ₂ = 19 / 39 answer : e"
Answer: E