Excluding the United States, the national mean number of holiday and vacation days in a year for OECD nations (see Exercise 3.6) is approximately bell shaped with a mean of 35 days and standard deviation of 3 days.3

(a) Use the Empirical Rule to describe the variability.

(b) The observation for the United States is 19. If this is included with the other observations, will the (i) mean increase, or decrease? (ii) standard deviation increase, or decrease?

(c) Using the mean and standard deviation for the other countries, how many standard deviations is the U.S.

observation from the mean?