The following data on gross efficiency (ratio of work accomplished per minute to calorie expenditure per
minute) for trained endurance cyclists were given in the
article “Cycling Efficiency Is Related to the Percentage of
Type I Muscle Fibers” (Medicine and Science in Sports
and Exercise
18.3 18.9 19.0 20.9 21.4 20.5 20.1 20.1
20.8 20.5 19.9 20.5 20.6 22.1 21.9 21.2
20.5 22.6 22.6 20.5 20.6 22.1 21.9 21.2
a. Assuming that the distribution of gross energy in the
population of all endurance cyclists is normal, give a point
estimate of m, the population mean gross efficiency.
b. Making no assumptions about the shape of the population
distribution, estimate the proportion of all such cyclists
whose gross efficiency is at most 20.