Using the 68-95-99.7 rule, what is the approximate percentage of lightbulb replacement requests numbering between 20 and 35

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 35 and a standard deviation of 5.

Answer 1

99,7/2 = 49.85% fall between 35 and 20

20 is 3 standard deviations from the mean. (35-20)/5= 15/5 = 3

99.7 % is for 20 to 50. 20 to 35 is half as much. the other half is 35 to 50