Find the probability that

Question

40% of graphic novels were purchased by readers who were 30 years of age or older. Fifteen readers are chosen at random. Find the probability that

a) at least 10 of them are 30 years or older

b) exactly 10 of them are 30 years or older

c) at most 10 of them are younger than 30

Answer 1

Use calculator:

a. 1-binomialcdf(15,.40,9)=0.0338.

b. binomialpdf(15,.40,10)=0.0245.

c. binomialcdf(15,.60,10)=0.7827.