Can You Solve the ‘Pink Triangle’ Math Problem That's Stumping the Internet?

iStock
iStock

Another day, another math problem that has all of social media scratching their collective heads. This one comes to us via Ed Southall, self-professed “maths bloke” and author of Geometry Snacks.

The question he poses is a simple one, albeit deceptively so: What fraction is shaded?

Though the main image is a simple square, that it’s broken down into four uneven “pieces” is what seems to be giving people the most trouble in figuring out the area of the pink shaded triangle.

Fortunately, hundreds of problem solvers were game to give the problem a try, and share how they came up with their answers with the Twitterverse—some of whom went full on Good Will Hunting on the problem:

Look closely at the solutions above and you’ll notice that they all come up with “1/3” as the answer, which is correct (even if they came to it in slightly different ways).

According to Business Insider reporter Andy Kiersz, the answer lies in figuring out the height of the pink triangle. “The key trick is that the little triangle up top is similar to the pink triangle, which means that the little triangle is just a smaller version of the pink triangle,” Kiersz wrote.

"A property of similar triangles is that the ratio of the triangles' heights will be the same as the ratio of their bases," Kiersz continues. "Since the pink triangle's base is twice the little triangle's base, its height is also twice the little triangle's height. But we know that the little triangle's height plus the pink triangle's height is 1, so that means the pink triangle's height is 2/3. Plug that on in and we get our area = 1/2 x base x height = 1/2 x 1 x 2/3 = 1/3."

(Southall confirmed that 1/3 is indeed the correct answer.)

[h/t: Business Insider]

This Inflatable Sloth Pool Float Is the Perfect Accessory for Lazy Summer Days

SwimWays
SwimWays

Summer is the perfect time to channel your inner sloth. Even if you don't plan on sleeping 15 to 20 hours a day, you can take inspiration from the animal's lifestyle and plan to move as little as possible. This supersized sloth pool float from SwimWays, spotted by Romper, will help you achieve that goal.

It's hard not to feel lazy when you're being hugged by a giant inflatable sloth. This floating pool chair is 50 inches long, 40 inches tall, and 36 inches wide, with two "arms" to support you as you lounge in the water.

One of the sloth's paws includes a built-in cup holder, so you don't have to expend any extra energy by getting up in order to stay hydrated. Unlike some pool floats, this accessory allows you to sit upright—which means you can drink, read, or talk to the people around you without straining your neck.

The sloth floatie is available for $35 on Amazon or Walmart. SwimWays also makes the same product in different animal designs, including a panda and a teddy bear. And if you're looking for a pool accessory that gives you even more room to spread out, this inflatable dachshund float may be just what you need.

People sitting in animal pool floats.
SwimWays

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