Here's the Answer to That Tasty 'Pi' Puzzle

Happy March 15, aka 'Day After Pi Day'!

Yesterday, on 'Pi Day' (aka 03/14, if we write out March 13 as the Americans do), we presented you with a puzzle from Brilliant.org.

It seemed deceptively simple, but there was something frustrating about it...

Here's what we told you: "Above, you'll see three identical boxes packed with pies. All the pies are exactly the same height."

The question was, which box contained the most pie?

Ready for the answer?

Because if you keep scrolling, you're gonna see it...

Last chance!

Okay, here's the answer: All three boxes contain the exact same amount of pie.

That's right. If you only guessed A, B or C, you were wrong. The right response was A, B and C.

Here's the explanation: Try looking at Box B as a single square box made from four smaller square boxes. Similarly, look at Box C as a square box made from 16 smaller square boxes. No matter the size of the box, the pie fills the exact same percentage. Therefore, pie fills the exact same percentage of each over-arching box.

Now, the 'pi' explanation: The area of a circle is pi x (radius)², or πr². If we refer to the radius of the small pies in Box C as r, we must refer to the radius of the medium pies in Box B as 2r and the radius of the large pi in Box A as 4r.

Some maths: The area of pie in Box A is π (4r)² = 16r2. The area of pie in Box B is 4 x π (2r)² = 16r2. Finally, the area of pie in Box C is 16π (r)² = 16r2.

Did you nail it?

Photo: iStock