The results of a survey of 1,154 adults showed that on average adults sleep 6.9 hours per day during the working week. Suppose that the standard deviation is 1.2 hours. If nothing is known about the...

The results of a survey of 1,154 adults showed that on average adults sleep 6.9 hours per day during the working week. Suppose that the standard deviation is 1.2 hours. If nothing is known about the shape of the relative frequency distribution a. calculate the percentage of individuals who sleep between 4.5 and 9.3 hours per day