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Fuel Economy (Updated!)

Are hybrid vehicles worth the extra cost?

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Fuel Economy (Updated!)

Are hybrid vehicles worth the extra cost?

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Fuel Economy - Student Handout.pdf
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Fuel Economy - Teacher Guide.pdf
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2023-2024 Versions

In the fall of 2024, Citizen Math released updated versions of every lesson in our library, plus a few new ones! We know you may have already prepped an earlier version or planned a repeat of last year, so we're continuing to make these earlier versions available through Thursday December 5, 2024.

You can find the new lessons through the regular search, and we hope you love them as much as we do. You can read more about these updates in Our Community.

Are hybrid cars worth the extra cost? Many vehicles are available with both standard gas-powered engines or hybrids. While the hybrid models require less gas and are better for the environment, they may initially cost thousands of dollars more.

In this lesson, students use linear equations to compare the costs of driving a car with a standard engine versus a hybrid engine and debate whether new buyers should always go green

REAL WORLD TAKEAWAYS

  • Hybrid cars use an electric motor at slower speeds which burns less fuel, causing less air pollution, than a gas powered one.
  • Hybrids cars typically cost more up front than their standard versions but require buying less gas to travel the same distance.
  • Which car is a better deal depends on how much one drives, how those miles are divided over the city and highway, and how long they plan to keep the car.

MATH OBJECTIVES

  • Write and solve equations to solve real-world questions
  • Compare proportional relationships represented in different forms including: tables, graphs, and equations
Appropriate most times as students are developing conceptual understanding.
Grade 8
Solving Linear Equations
Grade 8
Solving Linear Equations
Content Standards 8.EE.7 Solve linear equations in one variable. (a) Give examples of linear equations in one variable with one solution, infinitely many solutions, or no solutions. Show which of these possibilities is the case by successively transforming the given equation into simpler forms, until an equivalent equation of the form x = a, a = a, or a = b results (where a and b are different numbers). (b) Solve linear equations with rational number coefficients, including equations whose solutions require expanding expressions using the distributive property and collecting like terms. 8.F.4 Construct a function to model a linear relationship between two quantities. Determine the rate of change and initial value of the function from a description of a relationship or from two (x, y) values, including reading these from a table or from a graph. Interpret the rate of change and initial value of a linear function in terms of the situation it models, and in terms of its graph or a table of values.
Mathematical Practices MP.1 Make sense of problems and persevere in solving them. MP.4 Model with mathematics. MP.5 Use appropriate tools strategically.

Other Grade 8 Lessons

Domino Effect (Updated!)

How much does Domino’s charge for pizza?

Grade 8
Writing Linear Equations
Great anytime, including at the beginning of a unit before students have any formal introduction to the topic.

You're So Fined (Updated!)

How do municipal fines affect people with different incomes?

Grade 8
Solving Linear Systems
Great anytime, including at the beginning of a unit before students have any formal introduction to the topic.

Square Dancing (Updated!)

What secrets are hidden in squares?

Grade 8
Squares, Roots, Irrationals
Great anytime, including at the beginning of a unit before students have any formal introduction to the topic.

Sweet Tooth (Updated!)

How much Halloween candy should you eat?

Grade 8
Functions
Great anytime, including at the beginning of a unit before students have any formal introduction to the topic.

Timber (Updated!)

What size tree should we use for lumber?

Grade 8
Cones, Cylinders, Spheres
Appropriate most times as students are developing conceptual understanding.

Domino Effect (Updated!)

How much does Domino’s charge for pizza?

Grade 8
Writing Linear Equations
Great anytime, including at the beginning of a unit before students have any formal introduction to the topic.

You're So Fined (Updated!)

How do municipal fines affect people with different incomes?

Grade 8
Solving Linear Systems
Great anytime, including at the beginning of a unit before students have any formal introduction to the topic.

Square Dancing (Updated!)

What secrets are hidden in squares?

Grade 8
Squares, Roots, Irrationals
Great anytime, including at the beginning of a unit before students have any formal introduction to the topic.

Sweet Tooth (Updated!)

How much Halloween candy should you eat?

Grade 8
Functions
Great anytime, including at the beginning of a unit before students have any formal introduction to the topic.

Timber (Updated!)

What size tree should we use for lumber?

Grade 8
Cones, Cylinders, Spheres
Appropriate most times as students are developing conceptual understanding.