Q:

The GRE is an entrance exam that most students are required to take upon entering graduate school. In 2014, the combined scores for the Verbal and Quantitative sections were approximately normally distributed with a mean of 310 and a standard deviation of 12.What percent of scores were between 286 and 322? Round your answer to the nearest whole number.

Accepted Solution

A:
82% of the scores will be between 286 and 322.

To find this answer, we need to find the z-scores for 286 and 322. This is done by diving the difference from the mean by the standard deviation.

(286 - 310) / 12 = -2 which gives a percent of 2.28%
(322 - 310) / 12 = 1 which gives a percent of 84.13%

Subtracting those 2 percents will tell us the difference between the two scores.

84.13 - 2.28 = 81.85% or about 82%