To maintain their physical fitness, Americans are exercising more than ever in a variety of ways. Bradley and Robbins interviewed many Americans to determine how the were exercising. In How American Exercise, they present the following: 53% jog, 44% swim, 46% cycle, 18% jog and swim, 15% swim and cycle, 17% jog and cycle, and 7% jog, swim, and cycle. If an American who exercises regularly is randomly selected, what is the probability that the person either jogs, swims or cycles but does not do any more than 1 of those activities?

Farmers know that driving heavy equipment on wet soil compresses the soil and injures future crops. here are data on the "penetrability" of the same type of soil at two levels of compression. penetrability is a measure of how much resistance plant roots will meet when they try to grow through the soil. compressed soil 2.85 2.66 3 2.82 2.76 2.81 2.78 3.08 2.94 2.86 3.08 2.82 2.78 2.98 3.00 2.78 2.96 2.90 3.18 3.16 intermediate soil 3.17 3.37 3.1 3.40 3.38 3.14 3.18 3.26 2.96 3.02 3.54 3.36 3.18 3.12 3.86 2.92 3.46 3.44 3.62 4.26 use the data, omitting the high outlier, to give a 95% confidence interval for the decrease in penetrability of compressed soil relative to intermediate soil. compute degrees of freedom using the conservative method. interval: to