The one-time fling! Have you ever purchased an article of clothing (dress, sport
ID: 3132843 • Letter: T
Question
The one-time fling! Have you ever purchased an article of clothing (dress, sports jacket, etc.), worn the item once to a party, and then returned the purchase? This is called a one-time fling. About 5% of all adults deliberately do a one-time fling and feel no guilt about it! In a group of seven adult friends, what is the probability of the following? (Round your answers to three decimal places.)
(a) no one has done a one-time fling
(b) at least one person has done a one-time fling
(c) no more than two people have done a one-time fling
Explanation / Answer
PROBABILITY OF DOING ONE TIME FLING = 0.05
PROBABILITY OF NOT DOING ONE TIME FLING = 1-0.05 = 0.95
WE HAVE N = 7
A) P(X=0, NO ONE DONE FLING) = 7C0*(0.05)^0*(0.95)^7 = 0.698
B)P( AT LEAST ONE PERSON DONE IT) = 1 - P( 0 PERSON DONE IT) = 1 - 0.698 = 0.302
C) P(<=2) = P(0)+P(1)+P(2)
P(1) = 7C1*(0.05)^1*(0.95)^6 = 0.257
P(2) = 7C2*(0.05)^2*(0.95)^5 = 0.040
THEREFORE P(X<=2) =
= 0.698 + 0.040 + 0.257 = 0.995