Find the area of the shaded region.

Question

The graph to the right depicts IQ scores of adults, and those scores are normally distributed with a mean of 100 and a standard deviation of 15

Between 106 and 128

Answer 1

find the z scores, IQ minus mean IQ all divided by the standard deviation

(106-100)/15 = 6/15 = 2/5 = 0.4

(128-100)/15 = 28/15 = 1.8666... = about 1.87

use a z calculator online, such as desmos

plug in the 2 z scores and it gives you the area below the normal curve between those two z scores

area = approximately 0.3136