A railway enthusiast simulates train journeys and records the number of minutes, x, to the nearest minute, trains are late according to the schedule being used. A random sample of 50 journeys gave the following times. 17 5 3 10 4 3 10 5 2 14 3 14 5 5 21 9 22 36 14 34 22 4 23 6 8 15 41 23 13 7 6 13 33 8 5 34 26 17 8 43 24 14 23 4 19 5 23 13 12 10 Given that Ex-738 and Ex216 526, calculate to two decimal places, unbiased estimates of the mean and the variance of the population from which this sample was drawn. (L)