Q-T-Pi Fashions.....A Lesson About Using Credit Wisely



 Today's teens are frequently offered credit cards through the mail, and the temptation to "buy now--pay later" for instant gratification, may be quite compelling. This lesson illustrates how quickly credit card purchases can create a dangerous situation for buyers. This is a hands-on lesson that assumes the students understand and have used spreadsheets.


Primary Learning Outcome:

The students will be able to analyze the pros and cons of credit card use and describe how finance charges and monthly payment amounts effect the overall purchase price of items.


Assessed QCC:

Topic: Pattern, Sequence
Standard: Uses scientific calculator and computer skills to solve problems, to discover patterns and sequences, to investigate situations and draw conclusions.
Topic: Research, Investigation, Data Analysis
Standard: Uses computer software and applications to research, investigate, and analyze data and to represent this information using charts, tables, graphs, or other presentation forms.



Non-Assessed QCC:

Topic: Appropriate Methods and Tools, Applications
Standard: Solves problems, reasons, and estimates throughout mathematics.
Topic: Problem Solving
Standard: Selects and uses appropriate problem-solving strategies to solve single- and multi-step problems.



*Total Duration:

One 50-minute class period


Materials and Equipment:

  1. Calculators

  2. Computers

  3. Q T Pi FashionsWorksheet

Technology Connection: 

Microsoft Excel



Step One

  1. Define the terms credit, finance charges, interest, credit limit, incentive and annual percentage rate (APR).

  2. Discuss the definitions to ensure that the students have a good understanding of these terms.

Estimated Time:

10 minutes


Step Two

  1. Hand out the Q T Pi FashionsWorksheet to the students and read the introduction together.

  2. Students will work in groups of 2 to complete the first balance sheet and the answers to questions 1-4. They should use a calculator for computations. Note: For computation purposes, all figures are rounded to the nearest 100 and the 1.75% interest and finance rate has been rounded to a .081

  3. After the students have completed the task, show how the same information can be inserted into a spreadsheet for computation purposes. Click here to view the spreadsheet.

  4. Discuss answers to questions 1 through 4.

  5. Discuss the pros and cons of using a spreadsheet versus a calculator.

Estimated Time:

20 minutes



Step Three

  1. Students should complete the chart on page 3 of the handout using a spreadsheet and answer questions 5-8.

  2. Discuss the set up of the spreadsheet and the answers to the questions. Click here for spreadsheet.

Estimated Time:

20 minutes




Q T Pi Fashions requires a minimum 10% payment on any unpaid balances. The students should create a spreadsheet to answer the following question: If Credita only paid the minimum required each month, how many months would it take for her to pay her balance?


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