Question
In a region, 90% of the population have brown eyes. If 15 people are randomly selected, find the probability that at
least 13 of them have brown eyes. Is it
unusual to randomly select 15 people and find that at least 13 of them have brown eyes? Why or why not?
least 13 of them have brown eyes. Is it
unusual to randomly select 15 people and find that at least 13 of them have brown eyes? Why or why not?
Answers
Kuai
P(X ≥ 13) = P (X= 13) + P (X = 14) + P (X = 15)
P(X ≥ 13) =(15C13)(.9)^13(.1)^2+ (15C14)(.9)^14(.1)^1+ (15C15)(.9)^15(.1)^0
= .8159
P(X ≥ 13) =(15C13)(.9)^13(.1)^2+ (15C14)(.9)^14(.1)^1+ (15C15)(.9)^15(.1)^0
= .8159