Density of the earth In 1798, the English scientist Henry Cavendish measured the density of the earth several times by careful work with a torsion balance.

The variable recorded was the density of the earth as a multiple of the density of water. Here are Cavendish’s 29 measurements:12 5.50 5.61 4.88 5.07 5.26 5.55 5.36 5.29 5.58 5.65 5.57 5.53 5.62 5.29 5.44 5.34 5.79 5.10 5.27 5.39 5.42 5.47 5.63 5.34 5.46 5.30 5.75 5.68 5.85

(a) Enter these data into your calculator and make a histogram.

Include a sketch of the graph on your paper.

Then calculate one-variable statistics. Describe the shape, center, and spread of the distribution of density measurements.

(b) Calculate the percent of observations that fall within 1, 2, and 3 standard deviations of the mean. How do these results compare with the 68–95–99.7 rule?

(c) Use your calculator to construct a Normal probability plot. Include a sketch of the graph on your paper. Interpret this plot.

(d) Having inspected the data from several different perspectives, do you think these data are approximately Normal? Write a brief summary of your assessment that combines your findings from parts (a)

through (c).