The Empirical Rule The following data represent the length of eruption for a random sample of eruptions at the Old Faithful geyser in Calistoga, California.
|
108
|
108
|
99
|
105
|
103
|
103
|
94
|
|
102
|
99
|
106
|
90
|
104
|
110
|
110
|
|
103
|
109
|
109
|
111
|
101
|
101
|
|
110
|
102
|
105
|
110
|
106
|
104
|
|
104
|
100
|
103
|
102
|
120
|
90
|
|
113
|
116
|
95
|
105
|
103
|
101
|
|
100
|
101
|
107
|
110
|
92
|
108
|
(a) Determine the sample standard deviation length of eruption.
Express your answer rounded to the nearest whole number.
(b) On the basis of the histogram drawn in Section 3.1, Problem 28, comment on the appropriateness of using the Empirical Rule to make any general statements about the length of eruptions.
(c) Use the Empirical Rule to determine the percentage of eruptions that last between 92 and 116 seconds.
(d) Determine the actual percentage of eruptions that last between 92 and 116 seconds, inclusive.
(e) Use the Empirical Rule to determine the percentage of eruptions that last less than 98 seconds.
(f) Determine the actual percentage of eruptions that last less than 98 seconds.