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in an article about investment alternatives, money magazine reported that drug stocks provide a potential for long-term growth, with over 54% of the adult population of the united states taking prescription drugs on a regular basis. for adults age 65 and older, 85% take prescription drugs regularly. for adults age 18 to 64, 45% take prescription drugs regularly. the age 18–64 age group accounts for 84.5% of the adult population (statistical abstract of the united states, 2008).

round your answers to 4 decimal places.

a. what is the probability that a randomly selected adult is 65 or older?

b. given an adult takes prescription drugs regularly, what is the probability that the adult is 65 or older?

Which scenarios are most effectively explored by conducting an experiment? there is more than one correct answer. select all that apply. researchers want to study the effectiveness of a particular drug for treating migraines. they want to know which dosage of the drug yields the best results with the least side effects. to ensure fair results, the researchers want to ensure that participants and dosage administrators do not know which dosage participants receive. a teacher wants to plan a class fieldtrip and quickly determine where students prefer to go for the class fieldtrip. a car mechanic wants to know which of two engine brands makes better-performing engines. he wants to test the engines in identical situations and rate their performance in a way that can be fairly measured. a chemist studies the properties of a metal compound. she wants to know how the sample size of the metal affects its ability to conduct electricity. she wants to conduct the research in a controlled environment to minimize bias. a realty company wants to know the average income of its clients. the company wants to gather data income from current clients.