A bag contains 5 red, 8 black and 10 green balls. Two of them are taken out, find the probability that none of them is red.
1
111/221
2
117/217
3
153/253
4
135/247
5
None of these
A bag contains 5 red, 8 black and 10 green balls. Two of them are taken out, find the probability that none of them is red.