Pizzas

Act 1

Possible questions:

• Is the price fare?
• What would cost a pizza with diameter equal to 1 meter?
• Can you estimate the grams per person? What if we cut the pizza in 8 slices?
• In a square dish what percentage of dish the pizza would cover?

Act 2

• Price and diameter of each pizza
• Extract from original menu list if you want to do the same for different pizzas

Notes

• It is useful to have a discussion about the fairness of the price if we attend to the diameter (proportional reasoning). But if we reflect that the external corona of the circle contains more pizza than inner circle and when we double the diameter the mass of the pizzas does not double. Thus, we could attend the area of the pizzas. This way the price is more fair but not completely fair.
• We can do a simulation with geogebra about the price of the pizza depending on its diameter. This would give us the concept of the ratio of price respect to the area or diameter. And also it could involve the line which has the points $(diam_1, price_1)$ and $(diam_2, price_2)$.

About this document

The author of this work is Xavier Bordoy. This work is distributed under CC-BY-NC-SA 4.0 license. Its date of creation is 2021-06-29.

The pizza image is extracted from Alexis Bailey “Pizza” which is licensed under CC-BY 4.0 license.

This work has keywords: “proportional reasoning”, “circumference - circle”, “area”, “fractions”, .