Question

The maintenance department at the main campus of a large state university receives daily requests to replace fluorecent lightbulbs. The distribution of the number of daily requests is bell-shaped and has a mean of 50 and a standard deviation of 7. Using the 68-95-99.7 rule, what is the approximate percentage of lightbulb replacement requests numbering between 29 and 50? Do not enter the percent symbol. ans = %

Answer 1

Given that ,

mean = = 50

standard deviation = = 7

a)

By using empirical rule,

- 3 = 50 - 3*7 = 29

and

= 50

P( Between 29 and 50 ) = 2.35% + 13.5% + 34%

= 49.85%

The approximate percentage of lightbulb replacement requests numbering between 29 and 50 is 49.85