For the data in Exercise 3.20, determine the percentage of observations that fall within k = 1.5

Question:

For the data in Exercise 3.20, determine the percentage of observations that fall within k = 1.5 standard deviation units from the mean. Do the results support Chebyshev’s theorem?
In Exercise
For a sample of 11 employers, the most recent hourly wage increases were 18, 30, 25, 5, 7, 2, 20, 12, 15, 55, and 40 cents per hour.