Shopping Math: Percentages and Discounts Explained in Three Animated Videos

Includes animated videos

If you find yourself doing some frantic, last minute holiday shopping this weekend, you’re likely to run head-first into a stew of math.

Take that $130 pair of shoes you’ve been eyeing. Let’s say Macy’s just marked it down 20%. And on top of that, you’ve got a coupon for 10% off your entire purchase. So, you’re looking at a sweet discount of 10% off 20% off $130.

So … how much are those shoes going to cost you?

From sports to the news, to — most importantly — shopping, percentages are hard to avoid. To help make sense of it all, animator-explainer extraordinaire Josh Kurz breaks down the basic math behind everyday percentage conundrums (including the answer to this question).

Part I: The Basics

Part II: The Math of Discounts (or, Finding A Good Deal)

Part III: Combining Percentages (or, Finding A Good Deal)


Josh Kurz started out as an embryo, 53 times smaller than a US nickel. Born and raised in Brooklyn, New York, he began at an early age fusing the abstract concepts of science and comedy. Now he works as an independent filmmaker specializing in humorous science explainers ranging from the economics of voting to why some people (like he himself) hate cilantro. His work has been featured on WGBH, ABC, PBS, NPR, TEDed, and Radiolab.

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