EXAMPLE 6 Finding the percentile below a particular value

Returning again to the distribution of SAT scores, if Ting obtains a score of 430 on this exam, what percentage of individuals score the same as or lower than Ting? To answer this question, we must first convert Ting’s score to a standard score. This standard score is

306

From Table B, we can see that the standard score of −0.7 corresponds to a percentile of 24.20. Therefore, 24.20% of those individuals who took this exam score at or below Ting’s score of 430.