Question 1206171
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The physical plant at the main campus of a large state university receieves daily requests 
to replace {{{highlight(cross(florecent))}}} <U>fluorescent</U> lightbulbs. The distribution of the number of daily requests 
is bell-shaped and has a mean of 51 and a standard deviation of 3. 
Using the Empirical Rule rule, what is the approximate percentage of lightbulb replacement 
requests numbering between 42 and 51?
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Notice that in this problem 42 is three standard deviations from the mean of 51.


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 percentage of lightbulb 
replacement requests numbering between 42 and 51 is half of 99.7%, i.e. 49.85%.    <U>ANSWER</U>
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Solved.