Question

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 37 and a standard deviation of 7. Using the Empirical Rule rule, what is the approximate percentage of lightbulb replacement requests numbering between 37 and 58?

Answer 1

Solution :

Given that,

= 37

= 7

Using Empirical rule,

P( - 1< X < + 1) = 68%

P( - 2< X < + 2) = 95%

P( - 3< X < + 3) = 99.7%

P(37 < x < 58) = P(x < 58) - P(x < 37)

= 0.9985 - 0.5 = 0.4985 = 49.85%