At the US Open Tennis Championship a Statistician Keeps Track of Every

question 101

Multiple Choice

At the U.S. Open Tennis Championship a statistician keeps track of every serve that a player hits during the tournament. The statistician reported that the mean serve speed was 100 miles per hour (mph) and the standard deviation of the serve speeds was 15 mph. If nothing is known about the shape of the distribution, what percentage of the player's serve speeds are less than 70 mph?

• A) approximately 2.5%
• B) at most 12.5%
• C) at most 11%
• D) at most 25%
• E) approximately 5%

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Definitions:

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An economist hailing from Britain, whose groundbreaking ideas redefined the scope of macroeconomics and governmental policy initiatives.

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A 19th-century philosopher, economist, and revolutionary socialist who developed the theory of Marxism, focusing on the conflicts within capitalism and its eventual overthrow.

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An influential American economist known for his strong belief in free-market capitalism and for his role in the development of monetarism.

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