Assume that in a marketing study it has been found that on a fall Saturday after
ID: 3128020 • Letter: A
Question
Assume that in a marketing study it has been found that on a fall Saturday afternoon 20% of adult men watch sports programming on network A from 1:00 P.M. to 2:00 P.M., 25% watch on network C from 2:00 P.M. to 3:00 P.M., and 10% watch on both networks. For simplicity assume that viewers of these programs are sure to see advertisements if they are watching a program. If Chips ‘n’ Fish Restaurants advertise only on network C during the sports programming segment, (a) what is the probability that the ad will be seen by a randomly chosen adult man? (b) What would be the probability if they advertise on both networks? (c) If they advertise on both networks, what is the probability that an ad will be seen only on network A?
Explanation / Answer
Let A : Adult man who watch network A
B : Adult man who watch network B
P(A) = 0.2 ; P(B) = 0.25 ; P(A and B) = 0.1
a.) P( ad will be seen by a randomly chosen man)
= P( he watches network C)
= P(B)
= 0.25
B.) P( they advertise on both networks)
= P( A) + P(B) - P(A and B)
= 0.2 + 0.25 - 0.1 = 0.35
c.) P( ad will be seen only on network A | they advertise on both networks)
= 0.2/0.35 = 4/7