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

question 71

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

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Definitions:

Periodic Inventory System

An inventory accounting system where updates to inventory levels are made periodically, typically at the end of an accounting period.

Backpacks

Portable bags carried on one's back, designed to hold items such as books, supplies, or other personal belongings.

Credit

An entry recording an increase in liabilities or equity, or a decrease in assets, reflecting the business transactions' effects on the accounts.

Merchandise

Goods that are bought and sold in the course of business, typically in a retail or wholesale environment.