Question

Geologists recorded the duration (in seconds) of over 500 recent eruptions of the Old Faithful geyser in

Yellowstone National Park. Here's a histogram showing the distribution of their data:
= 210
0.26
0.22
0.18
0.15
Relative frequency
0.11
0.07
0.04
0.00
75
300
150 225
Duration (seconds)
Suppose that we were to take random samples of 30 eruptions from this population and calculate į as the
sample mean duration of the eruptions in each sample.
Which graph shows the most reasonable approximation of the sampling distribution of ?

Answer 1

Answer: C (A unimodal histogram, and the dotted line lands at 210)

Explanation:

Khan Academy - “The sample size is reasonably large (n = 30 _> 30), so the sampling distribution of x will be approximately normal even though the population isn’t.”