Algebra

Mr. Smith has 100 students in his Algebra classes. The grades of a quiz are normally distributed with a mean of 70 and a standard deviation of 4. Sally claims that 75 students scored between 66 and 74 on this quiz. Given that this is normally distributed, is Sally correct?

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  1. I thought I already answered this.

    Z = (score-mean)/SD

    Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion/probability between the two Z scores. Is it .75?

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