Here are the IQ test scores of a sample of 12 seventh-grade girls in a Midwestern...

Here are the IQ test scores of a sample of 12 seventh-grade girls in a Midwestern school district:

114	105	86	96
89	120	103	93
114	128	107	100

What are the mean and standard deviation of these IQ scores?

What proportion of the scores is within one standard deviation of the mean? What proportion of the scores is within two standard deviations of the mean?

What would we expect the proportions in part (b) to be if the scores followed a Normal distribution?

Is the true distribution of scores close to a Normal distribution or not? In your opinion, would it be reasonable to claim that IQ test scores follow a Normal distribution?

Expert Solution

a) From the given data

b)

orchestra answered 2 years ago

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