MATH Monday: Exponential Decay in Purchasing Power

Nov 15, 2020

Inflation lowers the purchasing power of your money over time.  This means that $100 today will be able to buy less in the future.  This is an important concept to understand so students can make decisions on where to save or invest their money to outpace inflation.  Inflation rates change year to year but over the long term can be modeled using exponential decay.


  1. View the MATH Collection: In today’s math activity, students will learn how to calculate percent change! Check it out in MATH: Exponential Decay in Purchasing Power.
  2. Example: Students can use this step-by-step example to practice exponential decay problems.

3. Bring in Real World Application: Your students can also review this Visual Capitalist Inflation Infographic that demonstrates a decade of grocery prices for 30 common items.


4. For Your Learning: Join Abby for Virtual PD on Tuesday 5pm PT as she reviews Teaching Remotely: MATH Collection Activities.

About the Author

Abby Alcala

After graduating with a statistics major at UC Davis, Abby set off to Massachusetts to teach algebra 1 and geometry and enjoyed working with the curious and creative minds of high school students. She is passionate about helping students recognize and develop their strengths and leadership skills. She was instrumental in taking the high school cheer team to regional competitions, as well as elevating school spirit and pride through creating unity amongst the study body and educators. Back in the Bay Area, Abby is excited to work with other educators to build and share content to enhance the teaching experience in applied math and finance.