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The physical plant at the main campus of a large state university recieves daily requests
to replace florecent lightbulbs. The distribution of the number of daily requests is
bell-shaped and has a mean of 46 and a standard deviation of 4.
Using the Empirical Rule rule, what is the approximate percentage of lightbulb replacement
requests numbering between 46 and 58?
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Notice that in this problem 58 is three standard deviations from the mean of 46.
The Empirical Rule states that 99.7% of data observed following a normal distribution
lies within 3 standard deviations of the mean.
Since the normal distribution is symmetric, we may conclude that the pecentage of lightbulb
replacement requests numbering between 46 and 58 is half of 99.7%, i.e. 49.85%. ANSWER
Solved.