EXAMPLE 7 Finding the percentile above a particular value

If Jordan scores 725 on the SAT Mathematics college entrance exam, what percentage of individuals would score at least as high or higher than Jordan? To answer this question, we must again begin by converting Jordan’s score to a standard score. This standard score is

To use Table B, we must first round 2.25 to 2.3. From Table B, we can see that the standard score of 2.3 corresponds to a percentile of 98.93. We might be tempted to assume our final answer will be 98.93%. If we were attempting to determine the percentage of individuals who scored 725 or lower, our final answer would be 98.93%. We want to know, however, the percentage who score 725 or higher. To find this percentage, we need to remember that the total area below the Normal curve is 1. Expressed as a percentage, the total area is 100%. To find the percentage of values that fall at or above 725, we subtract the percentage of values that fall below 725 from 100%. This gives us 100% − 98.93% = 1.07%. Our final answer is that 1.07% of individuals who take the SAT Mathematics college entrance exam score at or above Jordan’s score of 725.