Question

Based on data from a statistical abstract, only about 18% of senior citizens (65 years old or older) get the flu each year. However, about 23% of the people under 65 years old get the flu each year. In the general population, there are 14% senior citizens (65 years old or older). (Round your answers to three decimal places.)
(a) What is the probability that a person selected at random from the general population is senior citizen who will get the flu this season?



Incorrect: Your answer is incorrect.


(b) What is the probability that a person selected at random from the general population is a person under age 65 who will get the flu this year?



(c) Repeat parts (a) and (b) for a community that has 85% senior citizens.
(a)
(b)

(d) Repeat parts (a) and (b) for a community that has 52% senior citizens.
(a)
(b)

Answer 1

(a) The probability that a person selected at random from the general population is senior citizen who will get the flu this season is 0.14 x 0.18 = 0.0252

(b) The probability that a person selected at random from the general population is a person under age 65 who will get the flu this year is (1 - 0.14) x 0.23 = 0.86 x 0.23 = 0.1978

(c) (a) 0.85 x 0.18 = 0.153
     (b) (1 - 0.85) x 0.23 = 0.15 x 0.23 = 0.0345

(d) (a) 0.52 x 0.18 = 0.0936
     (b) (1 - 0.52) x 0.23 = 0.48 x 0.23 = 0.1104