Intelligence Quotients. IQs measured on the Weschlerrevised Intelligence Scale for children are supposed to have a standard deviation of 5 points. Twenty–five randomly selected children were given the IQ test; here are the data that were obtained.

93 88 93 101 92 92 96 96 95 110 100 102 94 103 86 97 87 102 89 97 95 103 97 81 102 Preliminary data analyses and other information indicate the reasonableness of presuming that IQs measured on the revised Weschler Intelligence Scale are normally distributed.

a. Do the data provide sufficient evidence to conclude that IQs measured on this scale have a standard deviation different from 5 points? Perform the required hypothesis test at the 10% significance level. (Note: s = 6.512.)

b. How crucial is the normality assumption for the hypothesis test you performed in part (a)? Explain your answer.