TABLE 2-5 The Following Are the Duration in Minutes of a Sample

question 147

Multiple Choice

TABLE 2-5
The following are the duration in minutes of a sample of long-distance phone calls made within the continental United States reported by one long-distance carrier.
-Referring to Table 2-5, what is the width of each class?

• A) 1 minute
• B) 5 minutes
• C) 2%
• D) 100%

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Definitions:

Confidence Interval

Range or interval of values with a stated probability of containing an unknown population parameter.

Mean

The mean is the average of a data set, calculated by adding all the numbers together and then dividing by the count of those numbers.

Confidence Limits

Lower and upper boundaries of a confidence interval.

Confidence Interval

A range of values, derived from sample data, that is likely to contain the value of an unknown population parameter.