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 55 and a standard deviation of 4. Using the empirical rule (as presented in the book), what is the approximate percentage of lightbulb replacement requests numbering between 51 and 55

Answer 1

percentage of lightbulb replacement requests = 34.15 %

Explanation:

According to Empirical Rule

interval %

μ ± σ 55 ± 4 ( 51 ; 59 ) 68.3

As the question is a percentage between 55 and 51

or between 51 and μ - σ by symmetry is 68.3/2

% of lightbulb replacement requests = 34.15 %