Question

IQ test scores scores on the Wechsler Adult Intelligence Scale (a standard IQ test ) for the 20 to 34 age group are approximately Normally distributed with μ=110 and σ=15. At what percentile is an IQ score of 130?

Answer 1

mean: 110

Standard deviation: 15

We have to apply the percentile formula:

z = (score- mean)/ standard deviation

z = (130-110)/15

z= 20/15

z= 1.3333333

Find the percentile with the z score in a z-score chart:

percentile: