A Random Sample of 56 Fluorescent Light Bulbs Has a Mean

question 95

Multiple Choice

A random sample of 56 fluorescent light bulbs has a mean life of 645 hours. Assume the population standard deviation is 31 hours. Construct a 95% confidence interval for the population mean.

• A)(636.9, 653.1)
• B)(539.6, 551.2)
• C)(112.0, 118.9)
• D)(712.0, 768.0)

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Definitions:

Standard Deviation

An indicator used to assess the degree to which data points diverge or scatter around the average value.

Range

The difference between the highest and lowest values in a dataset, showing the spread of the data.

Mean

An average value that summarizes or represents the central tendency within a data set, determined by dividing the sum of all values by their count.

Mode

The value that appears most frequently in a data set.