**Title: **The Mathematics of Credit Cards (as an application of exponential equations)

**Discipline(s) or Field(s):** Mathematics

**Authors:** Kirthi Premadasa, Paul Martin, Clare Hemenway, University of Wisconsin-Marathon County

**Submission Date:** December 14, 2008

*Goals of the lesson:*

- Students will learn how to make basic interest calculations, when calculating the monthly payments and the monthly interest charges on credit card balances.
- Students will learn what “amortization” means and will learn to fill in an amortization table.
- Students will use logarithms to solve the exponential equations encountered in the calculations of the payment periods for different payment methods.
- Students will develop an insight to the advantages and the disadvantages of the different payment methods.