Use High School Math Information to Teach the “Rule of 82” and its applications

Columnist: Dr. Matthew Yip (Mathematician Prof.)

The “80-20 rule” means that the first 20% of the “effort” will get the first 80% of the “return”. Using the function to express the high school, first set the function to go through (0,0), (1,1) and (0.2,0.8), and then take it as an exponential function, that is, .

Substituting and, we have , that is, . Therefore, , where , is a function that represents the “80-20 rule”.

Below is the activity graph:

After establishing an activity that represents the “80-20 rule”, examples can be used to deepen students’ understanding. The following is an example:

Consider that there are 10 million people in the world who are majoring in math education.

Their “influence” follows the “80-20 rule”. The “influence” of the most “influential” person must cause the “influence” of all people. What percentage of “power”?

We only need to replace find , which means that the “influence” of the “powerful” person exceeded 10%!

This example allows students to experience the magic of the “80-20 Rule”!

For other extensions of the “80-20 rule”, see “Combining “Single Points” and “the 80-20 rule.”