A sample of size 40 yields the following sorted data. Note that I have x-ed out x(39) (the second largest number). This fact will NOT prevent you from answering the questions below.

14.1 46.0 49.3 53.0 54.2 54.7 54.7 54.7 54.8 55.4 57.6 58.2 58.3 58.7 58.9 60.8 60.9 61.0 61.1 63.0 64.3 65.6 66.3 66.6 67.0 67.9 70.1 70.3 72.1 72.4 72.9 73.5 74.2 75.3 75.4 75.9 76.5 77.0 x 88.9

a. Calculate range, IQR, and median of these data.

b. Given that the mean of these data is 63.50 (exactly) and the standard deviation is 12.33, what proportion of the data lie within one standard deviation of the mean?

c. How does your answer to (b) compare to the empirical rule approximation?