**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

- example calculation for a 3 year (36 month loan) of $14,000 at 6% interest would look like this:

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.