Section 1

Lesson 3: The Rule of 72

 

Focus

 

Albert Einstein is among the world’s greatest physicists and mathematicians. He’s the father of relativity and is popularly associated with the formula E = mc2. His formula links mass and energy and the harnessing of nuclear power.

 

In a related matter, Einstein claimed, “The most powerful force in the universe is compound interest.” In this lesson you will investigate the power of compound interest and discover and use a rule for estimating the length of time needed to double an investment.

 

Lesson Question

 

In this lesson you will investigate the following question:

• How can the Rule of 72 be used to solve compound interest problems?

Assessment

 

Your assessment for this lesson may include a combination of the following:

• course folder submissions from the Try This and Share sections of the lesson

• your contribution to the Mathematics 20-3 Glossary Terms and the Formula Sheet

• Lesson 3 Assignment (Save a copy of your lesson assignment to your course folder now.)

• the Project Connection

Materials and Equipment

• calculator