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Big Foot Conspiracy

Should people with small feet pay less for shoes?

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Big Foot Conspiracy

Should people with small feet pay less for shoes?

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Bigfootconspiracy lessonpage a
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Should people with small feet pay less for shoes? When you buy deli meat, the more you get, the more you pay. This isn’t the case with shoes, though. A pair of sneakers costs the same in size 6 as in size 12, even though it has less material.

In this lesson, students use unit rates to calculate how much different-sized shoes cost per ounce and debate the fairest way for manufacturers to charge for their shoes.

REAL WORLD TAKEAWAYS

  • While some products use fixed pricing (e.g. a t-shirt costs $15), others use unit pricing (e.g. tomatoes cost $4 per pound). Sometimes, it’s obvious which pricing system is appropriate; sometimes either might work, and the one we use is largely due to convention. We do it because it's the way we've always done it...but we could do it differently.
  • When buying products with fixed pricing that come in different sizes, people buying smaller sizes will get less material for the same price as someone buying a bigger size. However, there are many other drivers of cost for the company selling the product.
  • Pricing structures can affect human behavior, e.g. people might try to fit into smaller shoes if they were cheaper.

MATH OBJECTIVES

  • Calculate unit rate ($/oz) for various sized shoes and discuss how the cost per ounces changes as size changes
  • For a given cost per ounce, calculate how much different size shoes would cost if Nike charged by weight
  • Discuss advantages and disadvantages of alternative pricing schemes

Great anytime, including at the beginning of a unit before students have any formal introduction to the topic.
Lesson gauge easy
Grade 7
Ratios & Proportions
Lesson gauge easy
Grade 7
Ratios & Proportions
Content Standards
Mathematical Practices

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