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 60 and a standard deviation of 11. using the empirical rule rule, what is the approximate percentage of lightbulb replacement requests numbering between 60 and 71?

34%

Step-by-step explanation:

According to the Empirical rule,

About 68% of the population lies with in one standard deviation from the mean.

i.e. About  34% of the population lies above one standard deviation from the mean .

and About 34% of the population lies below one standard deviation from the mean.

Given : The distribution of the number of daily requests is bell-shaped ( i.e. Normally distribution) and has a mean of 60 and a standard deviation of 11.

i.e.

Using the Empirical Rule rule,  34% of the population of lightbulb replacement requests lies above one standard deviation from the mean .

i.e. About 34% of the population of lightbulb replacement requests lies between and

i.e. About   34% of the population of lightbulb replacement requests lies between and

i.e. About  34% of the population of lightbulb replacement requests lies between 60 and 71

Hence, the approximate percentage of lightbulb replacement requests numbering between 60 and 71 = 34%