103 7.3 Topic 3: Numerical Descriptive Statistics 18. In your own words, thoroughly describe the difference between the mean and median. 19. Explain in your own words what is measured by the standard...

Question 20 only, please

Extracted text: 103 7.3 Topic 3: Numerical Descriptive Statistics 18. In your own words, thoroughly describe the difference between the mean and median. 19. Explain in your own words what is measured by the standard deviation. 20. Suppose we have data on the ages of U.S. presidents. We also have ages for a sample of high school teachers. Which group would you expect the have a larger standard deviation and why? 21. Answer the following questions given the two histograms in Figure 7.5. Figure 7.5: Comparing the center and spread in histograms Histogram 1 Histogram 2 5 6 2 3 1 (a) Identify which has a larger standard deviation. Explain. (b) Do you expect the two means to be similar or will one mean be larger than the other? Explain. 22. Ages from a random sample of 18 athletes in the 2012 London Olympics is provided below. Ages are from athletes across any of the events. Calculate the following summary statistics to explor the distribution of ages for Olympic athletes. 21, 22, 26, 24, 32, 21, 21, 20, 22, 31, 34, 23, 27, 26, 29, 20, 22, 29 (a) Find the mean and median of the data. (b) Based on the mean and median, what can be said about the likely shape of the data? D this make sense given the setting for the data? Explain. (c) Which of the two measures of center is more appropriate for this data? Explain. (d) Find the standard deviation and IQR of the the data using the calculator. (e) Which of the two measures of spread is most appropriate for the data? Explain. 4- 2.