The Head Librarian at the Library of Congress Has Asked

question 174

Multiple Choice

The head librarian at the Library of Congress has asked her assistant for an interval estimate of the mean number of books checked out each day. The assistant provides the following interval estimate: from 740 to 920 books per day. If the head librarian knows that the population standard deviation is 150 books checked out per day, and she asked her assistant to use 25 days of data to construct the interval estimate, what confidence level can she attach to the interval estimate?

• A) 95.4%
• B) 99.7%
• C) 98.0%
• D) 99.0%

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Definitions:

NAFTA

The North American Free Trade Agreement, a treaty between Canada, Mexico, and the United States that removed tariff barriers between the nations.

GATT

The General Agreement on Tariffs and Trade, an international treaty that aimed to reduce tariffs and other trade barriers; precursor to the World Trade Organization.

Economists

Experts in the study of economics, focusing on the distribution, consumption, and production of goods and services.

Net Exports

The value of a country's total exports minus its total imports; a positive value indicates a trade surplus, while a negative value indicates a trade deficit.