2.) France conducts a study of families that visit the country each year as tourists. The fraction of such families of size m is 288−m. For a family of size m that visits France, the number of members of that family that visit Paris follows a discrete uniform distribution on the set 1,2,…,m. Calculate the probability that a family has exactly 6 members, given that exactly 5 members of that family visit Paris.
Q. 2.) France conducts a study of families that visit the country each year as tourists. The fraction of such families of size m is 288−m. For a family of size m that visits France, the number of members of that family that visit Paris follows a discrete uniform distribution on the set 1,2,…,m. Calculate the probability that a family has exactly 6 members, given that exactly 5 members of that family visit Paris.
Given Fraction of Families: We are given that the fraction of families of size m is (8−m)/28. We want to find the probability that a family has exactly 6 members, given that exactly 5 members visit Paris. This is a conditional probability problem, and we can use the formula P(A∣B)=P(A and B)/P(B), where A is the event that a family has exactly 6 members and B is the event that exactly 5 members visit Paris.
Calculate P(A): First, we calculate P(A), the probability that a family has exactly 6 members. We substitute m=6 into the fraction 288−m to find the probability of a family being of size 6.P(A)=288−6=282=141
Calculate P(B): Next, we calculate P(B), the probability that exactly 5 members visit Paris. Since the number of members that visit Paris follows a discrete uniform distribution on the set 1,2,...,m, the probability that any specific number of members visit Paris is m1. For a family of size 6, the probability that exactly 5 members visit Paris is 61. P(B)=61
Calculate P(A and B): Now, we calculate P(A and B), the probability that a family has exactly 6 members and exactly 5 members visit Paris. Since the events are independent (the size of the family does not affect the distribution of who visits Paris), we can multiply the probabilities of A and B.P(A and B)=P(A)×P(B)=141×61=841
Find P(A∣B): Finally, we use the conditional probability formula to find P(A∣B), the probability that a family has exactly 6 members given that exactly 5 members visit Paris.P(A∣B)=P(B)P(A and B)=1/61/84=841×16=846=141
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