Happen to be doing some frantic, last minute holiday shopping this weekend? If so, you’ll likely find yourself inadvertently diving head-first into a big 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 of everyday percentage conundrums (including the answer to the above question) — in three animated acts.

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.


Matthew Green

Matthew Green runs KQED’s News Education Project, an online resource for educators and the general public to help explain the news. The project lives at kqed.org/lowdown.

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