desaichinmay22
Probability of a person to be born in a leap year = 1/4 ... <1/2
Probability of atleast one person out of two to be born in a leap year = 1/4+1/4=1/2 .... not >1/2
Probability of atleast one person out of 3 to be born in a leap year = 1/4+1/4+1/4=3/4..... >1/2
Hence minimum 3 people are required.
Ans = C
I don't think, this is the right approach.
Probability of a person to be born in a leap year = 1/4 ... <1/2 (alright)
Probability of at least one person out of two to be born in a leap year = 1/4 x 3/4 +3/4 x 1/4 + 1/4 x 1/4 = 7/16 <0.5
Probability of at least one person out of 3 to be born in a leap year = 1 - negative of no one is born in leap year = 1- (3/4) x (3/4) x (3/4) = 37/64 >0.5
hence answer is C
It is better to use non event method in such questions. Reduces lot of efforts and saves time