At least 2 out of n people born on April 1 means either all n are not born on April 1 or exactly 1 born on April 1. So, P(X) = 1 - P(Y) - P(Z) where P(Y) is the probability that none are born on April 1 and P(Z) is the probability that exactly 1 is born on April 1 P(Y) = 364n/365n P( ... ) = 0.016 P(50) = 0.24 P(120) = 0.517 P(119) = 0.514 P(115) = 0.502 P(114) = 0.497 So, 115 would be the answer.
posted
May 30, 2018
in From GO Admins
Arjun
1,659 views
