5.34 Number of friends on Facebook. To commemorate Facebook’s10-year milestone, Pew Research reported several facts aboutFacebook obtained from its Internet Project survey. One was thatthe average adult user of Facebook has 338 friends. This populationdistribution takes only integer values, so it is certainly notNormal. It is also highly skewed to the right, with a reportedmedian of 200 friends. 8 Suppose that σ = 380 and you take an SRSof 80 adult Facebook users. For your sample, what are the mean andstandard deviation of x ¯, the mean number of friends per adultuser? Use the central limit theorem to find the probability thatthe average number of friends for 80 Facebook users is greater than350.
