68-95-99.7 Rule

1. In a mid-size company, the distribution of the number of phone calls answered each day by each of the 12 receptionists is bell-shaped and has a mean of 62 and a standard deviation of 7. Using the 68-95-99.7 Rule (as presented in the book), what is the approximate percentage of daily phone calls numbering between 41 and 83? 2, The distribution of the lifetime of a tire is bell-shaped. The mean lifetime of a tire is 40000 kilometers with a standard deviation of 5000 kilometers. a) About 68% of tires have a lifetime between__kilometers and kilometers bj b) About 95% of tires have a lifetime between_ _ kilometers and kilometers C. About 99.7% of tires have a lifetime between_kilometers and kilometers, 3.At a tennis tournament, a statistician keeps track of every serve. The statistician reported that the mean serve speed of a particular player was 65 miles per hour (mph) and the standard deviation of the serve speeds was 9 mph. Assume that the statistician also gave us the information that the distribution of the serve speeds was bell shaped. a) What is the approximate percentage of serves between 47 and 83? b. 99.7 % of the serves are between the bottom boundary_and the top boundary 4. The Acme Company manufactures widgets. The distribution of widget weights is bell-shaped. The widget weights have a mean of 60 ounces and a standard deviation of 8 ounces. Use the Empirical Rule and a sketch of the normal distribution in order to answer these questions, and a) 95% of the widget weights lie between b) What percentage of the widget weights lie between 36 and 76 ounces?_ () What percentage of the widget weights lie above 52