Question 69

Mathematics Probability Hard

If \( p \) is the probability that a man aged \( x \) will die in a year, then the probability that out of \( n \) men \( A_1, A_2, \dots, A_n \), each aged \( x \), man \( A_1 \) will die in a year and be the first to die is:

(A) \(\frac{1}{{n}^2}\)
(B) \(1-((1-p))^n\)
(C) \(\frac{1}{{n}^2}\lbrack{1-(1-p){{}^{}}^n}\rbrack\)
(D) \(\frac{1}{n}\lbrack{1-(1-p){}^n}\rbrack\)
View Dynamic Solution & Explanation
Correct Solution: Option D

Step-by-step Solution:

The probability that none of them will die is: \[ (1 - p)^n \] Hence, the probability that at least one of them will die is: \[ 1 - (1 - p)^n \] Now, if we consider the order, the probability that \( A_1 \) is the first to die among \( n \) people is: \[ \frac{1}{n} \left( 1 - (1 - p)^n \right) \]