Answer Happy

The physical plant at the main campus of a large state university receives daily requests to replace florescent light bulbs. The distribution of the number of daily requests is bell- shaped and has a mean of 56 and a standard deviation of 11. Using the empirical (68-95-99.7) rule, what is the approximate percentage of light bulb replacement requests numbering between 56 and 78? Do not enter the percent symbol. Caution: Using tables or Excel for this may produce a wrong answer. Use the 68-95-99.7 rule. Answer = % (Enter your answer as a percent, but do not enter the percent symbol. Do not enter in decimal form or round your answer. For example, enter 93.8 for 93.8%, not 0.939)
A company has a policy of retiring company cars; this policy looks at number of miles driven, purpose of trips, style of car and other features. The distribution of the number of months in service for the fleet of cars is bell-shaped and has a mean of 65 months and a standard deviation of 9 months. Using the empirical (68-95-99.7) rule, what is the approximate percentage of cars that remain in service between 74 and 92 months? Caution: Using tables or Excel for this may produce a wrong answer. Use the 68-95-99.7 rule. Answer = % (Do not enter the percent symbol or round your answer. This asks for a percentage so do not convert to decimal. For example, for 99%, you would enter 99, not 0.99)