54. Consider the following observations on shear strength (MPa)

of a joint bonded in a particular manner (from a graph in the article “Diffusion of Silicon Nitride to Austenitic Stainless Steel without Interlayers,” Metallurgical Trans., 1993:

1835–1843).

22.2 40.4 16.4 73.7 36.6 109.9 30.0 4.4 33.1 66.7 81.5

a. What are the values of the fourths, and what is the value of fs?

b. Construct a boxplot based on the five-number summary, and comment on its features.

c. How large or small does an observation have to be to qualify as an outlier? As an extreme outlier?

d. By how much could the largest observation be decreased without affecting fs?