Use the Empirical Rule. The mean speed of a sample of vehicles along a stretch of
highway is 64 miles per hour, with a standard deviation of 4 miles per hour. Estimate the
percent of vehicles whose speeds are between 52 miles per hour and 76 miles per
hour. (Assume the data set has a bell-shaped distribution.)
Approximately % of vehicles travel between 52 miles per hour and 76 miles per hour
