Mar 13, 2023

Pi Day Question of the Day: What pizza pie size did researchers find had the lowest price per sq. inch: 8-inch, 14-inch or 16-inch?

Which pizza pie would you choose on PI Day?

Answer: 16-inch pizza

Here's the ready-to-go slides for this Question of the Day that you can use in your classroom.

Questions: 

  • Now that you know that the 16-inch pizza is better value per square inch than the 8 or 14-inch pizza, would you plan to always buy it going forward? Why or why not?
  • Have you ever made pizza at home? How does the cost and value compare to buying pizza at a restaurant?
  • Bonus math question: What’s the formula for the area of a circle?

Behind the numbers (NPR):

The math of why bigger pizzas are such a good deal is simple: A pizza is a circle, and the area of a circle increases with the square of the radius. So, for example, a 16-inch pizza is actually four times as big as an 8-inch pizza. And when you look at thousands of pizza prices from around the U.S., you see that you almost always get a much, much better deal when you buy a bigger pizza.

------------------

Looking for another unit price activity? Look no further with this NGPF Data Crunch.

------------------

 Your class could win a bunch of 16-inch pizza pies with the FinCap Friday Frenzy contest. Find out the details

 

 

About the Author

Tim Ranzetta

Tim's saving habits started at seven when a neighbor with a broken hip gave him a dog walking job. Her recovery, which took almost a year, resulted in Tim getting to know the bank tellers quite well (and accumulating a savings account balance of over $300!). His recent entrepreneurial adventures have included driving a shredding truck, analyzing executive compensation packages for Fortune 500 companies and helping families make better college financing decisions. After volunteering in 2010 to create and teach a personal finance program at Eastside College Prep in East Palo Alto, Tim saw firsthand the impact of an engaging and activity-based curriculum, which inspired him to start a new non-profit, Next Gen Personal Finance.

author image More by Tim right solid arrow
Mail Icon

Subscribe to the blog

Join the more than 12,000 teachers who get the NGPF daily blog delivered to their inbox:

SIGN UP