A bag contains 5 red smileys, 6 yellow smileys and 3 green smileys. If two smileys are picked at random, what is the probability that both are red or both are green in colour?
Correct Answer: 1\/7
Given total number of smileys = 5 + 6 + 3 = 14
Now, required probability =
5C214C2 + 3C214C2 = 1091 + 391 = 1391 = 17