Real-Life Math -- Solution
You must determine how many people actually fall into these two ranges. Because this is based on a 100,000 population and 67 percent of people fall into the gradient 15 range, the easiest way to determine the answer is by using the following equation:
100,000 x 67 percent (or 0.67) = 67,000 people
The second range, which has a gradient of 18, is where an additional 12 percent of the population falls. The equation is almost the same as above:
100,000 x 12 percent (or 0.12) = 12,000 people
12,000 + 67,000 = 79,000 people have IQs between 82 and 118
Therefore, 79,000 people (out of a population of 100,000) have IQs between 82 and 118.
"A lot of math is used in our assessments as well as in our tests," says Corkum. So be prepared to keep up with your math skills. Not only will you need to be able to calculate equations, but you'll also need to be able to explain your answers to students and parents.