Old Faithful. Old Faithful is a geyser in Yellowstone National Park that erupts at relatively predictable intervals.

Since 2000, the eruptions of Old Faithfull occur on average every 90 minutes. Information on the daily eruptions of Old Faithful can be found on the website of The Geyser Observation and Study Association (GOSA). The following data provide the times between eruptions, in minutes, for Old Faithful over a two-day period.

96 68 99 97 92 61 105 89 95 71 93 104 85 107 91 97 99 86 102 93 99 64 102 86 101 81 117 87 106 93 106 106

a. Use cutpoint grouping with a first class of 60–under 70 to construct a frequency histogram of the times between eruptions.

b. Identify the shape of the distribution with regard to modality.

c. Identify the shape of the distribution with regard to symmetry (or nonsymmetry).

d. If the distribution is unimodal and nonsymmetric, classify it as either right skewed or left skewed.