Probability Question 317
Question: Probability that a man who is 40 year old, living till 75 years is 5/16, and another man who is 35 years old living till 70 years is 3/7 then what is the probability that at least one of them will be alive till 35 years hence?
Options:
A) 11/28
B) 19/28
C) 17/28
D) None of these
Show Answer
Answer:
Correct Answer: C
Solution:
Let A be the event that 1st man will be alive till 75 years and B be the event that 2nd man will be alive till 70 years then $ P(A)=5/16 $
and $ P(B)=3/7 $ then $ P(A’)=11/16 $ , and $ P(B’)=4/7 $
Probability that none of them will be alive 35 years hence is $ P(A’)xP(B’)=11/19x4/7=11/28 $
Then required probability is $ 1-11/28=17/28 $
BETA
