The Head Librarian at the Library of Congress Has Asked

question 154

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, approximately how large a sample did her assistant use to determine
The interval estimate?

• A) 2
• B) 3
• C) 12
• D) It cannot be determined from the information given.

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Definitions:

Illustration

A visual representation or example that helps explain or clarify something.

Frequency Distribution

A summary of data showing the number (frequency) of observations falling within specified intervals.

Cumulative Frequency

The sum of the frequencies of all values at or below a certain point in a dataset or frequency distribution.

Bar Chart

A visual representation of data where each category is represented by a bar, whose length reflects the category's value.