Mean, Median, and Mode of the Geyser Data

In this activity, you will be calculating the mean, median, and mode for the eruption data of the Old Faithful Geyser, located in Yellowstone National Park in Wyoming. Its name reflects the fact that it erupts on a very regular basis. The data consists of the number of the eruptions and length of time between them, collected over 16 days.

Using the data set in Excel, calculate the mean, median and mode for both the duration of the eruptions and the intervals between the eruptions.


1. What is the mean duration of the eruptions?
2. How much difference is there between the median duration of the eruptions and the mean duration?
3. What is the most frequent duration of the eruptions?
4. If you went to Yellowstone National Park to see Old Faithful, how long do you think you would likely have to wait between eruptions?
5. Explain how you came to your answer for question 4.

Sometimes, looking at data sets in a different way can reveal some interesting traits that were not detected by an initial analysis.

Using EXCEL, insert a scatter plot of duration data set and see what you discover!

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