Characteristic of Learning: Authentic
Level of Technology Infusion Into the Curriculum: Adoption
Lesson Title: Calculating A Monthly Car Payment
Grade Level: 11-12
Classroom Configuration
One to one, using classroom computers or mobile laptops as rotating stations
Common Core State Standards: Mathematics
Mathematical Practices
- Make sense of problems and persevere in solving them.
- Reason abstractly and quantitatively
- Use appropriate tools strategically
Statistics and Probability
Interpreting Categorical & Quantitative Data: Summarize, represent, and interpret data on a single count or measurement variable.
S.ID.2
Use statistics appropriate to the shape of data distribution to compare center (median, mean) and spread (inter-quartile range, standard deviation) of two or more different data sets
A.REI.1
Understand solving equations as a process of reasoning and explain the reasoning.
1. Explain each step in solving a simple equation as following from the equality of numbers asserted at the previous step, starting from the assumption that the original equation has a solution. Construct a viable argument to justify a solution method.
Arizona Educational Technology Standards (2009)
- Strand 4: Critical Thinking, Problem Solving, Decision Making
- Concept 1:Investigation,
- PO 1 Plan and manage data sets from diverse sources, creating planning adjustments and course corrections from knowledge gained.
- Strand 5 Digital Citizenship
- Concept 1: Safety and Ethics,
- PO 3 Advocate and practice safe, legal and responsible use of digital tools as defined by school board polices and procedures
Objectives
- The students will solve a real-world problem of calculating a monthly car payment by utilizing online tools.
- The students will calculate a monthly car payment by using a formula containing fractions, exponents, and order of operations from information acquired via online resources.
Procedure
- Students will research a car from an Internet used car dealer. Example sites to use: usedcars.com, AutoTrader, carmax
- Once students find a car, they will use the formula below to calculate a monthly payment.
- Students will experiment with the interest rates 6%, 8%, and 10%
- Students will also experiment with a 3 and 4 year loan length
- Students will calculate payment assuming there is no down payment, so the student must finance the entire price of the car.
- Key for formula: p = principal, r = interest rate, m = monthly payments
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- example calculation for a 3 year (36 month loan) of $14,000 at 6% interest would look like this:
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The payment for this car would be $ 425.91
- Students will use an online scientific calculator, if scientific calculators are not available
- Students will write down the setup for each loan configuration that they compute and explain how they arrived at their answers.
- Loan Configurations will be:
- 3 year loan at 6% interest
- 4 year loan at 6% interest
- 3 year loan at 7% interest
- 4 year loan at 7% interest
- 3 year loan at 8% interest
- 4 year loan at 8% interest
- Students will create a spreadsheet with the information via Google Tools or Zoho.
- The students will answer the following questions:
- Which car is the best deal? Defend your answer.
- Which car would you be most likely to purchase, why?
Materials
- Laptops with Internet access
- Google Spreadsheet (docs.google.com), Zoho (http://sheet.zoho.com/login.do?serviceurl=%2Fhome.do) or other tool of students choice
- Simple scientific calculator
Online Resources: http://www.usedcars.com/, http://www.autotrader.com/, http://www.calculator.com/calcs/calc_sci.html
Assessment
- Student work will be assessed by evaluating the calculations that students computed and their responses to the questions.
Extension: Have students do a comparison of cost between two cars they would most like to own. Record data in a spreadsheet program. They should include items to reflect total cost of ownership.