Find the Indicated Probability What Is the Probability That a Randomly Selected Person Was

question 221

Multiple Choice

Find the indicated probability.
-The following table show the results of a clinical trial for an allergy drug. $$\begin{array} { l | c | c | c | c } & \begin{array} { c } \text { Allergy } \\\text { drug }\end{array} & \text { Placebo } & \begin{array} { c } \text { Control } \\\text { (no treatment) }\end{array} & \text { Total } \\\hline \text { Improvement } & 145 & 85 & 41 & 271 \\\text { No improvement } & 55 & 115 & 59 & 229 \\\text { Total } & 200 & 200 & 100 & 500\end{array}$$ What is the probability that a randomly selected person was given a placebo or improved? Round your answer to the nearest thousandth when necessary.

• A)0.942
• B)0.17
• C)0.69
• D)0.772

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Definitions:

SEC

The Securities and Exchange Commission, a U.S. regulatory agency responsible for enforcing federal securities laws and regulating the securities industry.

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The profit realized from an investment after all applicable taxes have been subtracted.

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Malkiel's Study

An academic research work that analyzes market trends, investor behavior, and the efficiency of financial markets, particularly known for supporting the random walk hypothesis.