SOLUTION: The distribution of the heights of students in a large class is roughly normal. Moreover, the average height is 68 inches, and approximately 95% of the heights are between 62 and 7

Question 931119: The distribution of the heights of students in a large class is roughly normal. Moreover, the average height is 68 inches, and approximately 95% of the heights are between 62 and 74 inches. Thus the standard deviation of the height distribution is approximately equal to
A)2 B)3 C)6 D)9 E)12
Please help I'm stuck on how to work through this.
Answer by jim_thompson5910(35256) (Show Source): You can put this solution on YOUR website!
According to the empirical rule, roughly 95% of the distribution is within 2 standard deviations of the mean.

The mean is 68. The distance from 62 to 68 is 6 inches

Cut that in half to get 6/2 = 3

So the standard deviation is 3

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