Question

In an article about investment alternatives, Money Magazine reported that drug stocks provide a potential for long-term growth, with over fifty percent of the adult-population of the USA taking prescription drugs on a regular basis. For adults 65 and older, 82% take prescription drugs regularly. For adults age 18 to 64, 49% take prescription drugs regularly. The 18-64 group accounts for 83.5% of the adult population (Statistical Abstract of the United Staes, 2008).

a) GIVEN that an adult takes prescription drugs regularly, what is the probability that the adult is 65 or older?

Answer 1

Given that The drug stocks provi de a potential for long-term growth, with over 50% of the adult population of the United States taking prescription drugs on a regular basi s For adults age 65 and older, 82% take prescription drugs regularly For adults age 18 to 64, 49% take prescription drugs regularly The age 18-64 age group accounts for 83.5% of the adult popul ati on 18-64 65 and ol der Taking Prescription drugs | 0.40915 0.09085 50% on a regulaf basis Taking Prescription drugs | 0.42585 0.07415 50% not a regular basis 83.5% 16.5% 100% (a) The probability that a randomly selected adult is 65 or older is We have, the age 18-64 age group accounts for 83.5% of the adult population So, 100%-83.5% 16.5% Therefore, the probability that a randomly selected adult is 65 or ol der is 0.165 (b) We have to find the probability that the adult is 65 or older if an adult takes prescripti on drugs regularly adult takes prescripti on P adult 65 or older drugs regularly adult 65 or older and takes prescription drugs regularly adult takes prescription drugs regul arly 0.09085 0.50 - 0.181

Answer 2

a. Adults are made up of those 18-64 and those 65+
Thus,P(an adult is 65+) = 1 - P(an adult is 18-64) =
1 - .835 = .165 or 16.5%

b.For this problem, we need to figure the P(adult is 65 or older | the adult takes drugs) = P(adult 65 or older and takes drugs)/P(adult takes drugs)

The numerator equals .165 * .82
The denominator equals .165 * .82 + .835 * .49 (including those 65+ and those 18-64 taking drugs)

Then, P(adult is 65 or older | the adult takes drugs) =
.165 * .82/(.165 * .82 + .835 * .49 ) = 0.248507668 = .249 = 24.9%.

Answer 3

a. Adults are made up of those 18-64 and those 65+
Thus,P(an adult is 65+) = 1 - P(an adult is 18-64) =
1 - .835 = .165 or 16.5%

b.For this problem, we need to figure the P(adult is 65 or older | the adult takes drugs) = P(adult 65 or older and takes drugs)/P(adult takes drugs)

The numerator equals .165 * .82
The denominator equals .165 * .82 + .835 * .49 (including those 65+ and those 18-64 taking drugs)

Then, P(adult is 65 or older | the adult takes drugs) =
.165 * .82/(.165 * .82 + .835 * .49 ) = 0.248507668 = .249 = 24.9%.