Task 15: In Chapter 1 (Task 9) we looked at the length in days of nine celebrity marriages. Here are the length in days of eight marriages, one being mine and the other seven being those of some of my friends and family (in all but one case up to the day I’m writing this, which is 8 March 2012, but in the 91-day case it was the entire duration – this isn’t my marriage, in case you’re wondering): 210, 91, 3901, 1339, 662, 453, 16672, 21963, 222. Calculate the mean, standard deviation and confidence interval for these data. ②