About what percent of the students taking the test have scores between 68 and 82?

Question

The scores on a college history exam are normally distributed with a mean of 75 and a standard deviation of 7. The test scores range from 0 to 100. About what percent of the students taking the test have scores between 68 and 82?

Answer 1

Hi Chris. 68 and 82 both represent one standard deviation from the left and the right of the mean in the Bell Curve. That means you would add 15.0% and 19.1% from the left side of mean, to another 15.0% and 19.1% from the right side of the mean.

That means that 68.2% (total from above) of the students scored between 68 and 82.

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