The area of a triangle is 1/2(b)(h), where b is the base and h is the height.

What that means is that a triangle can have the same area with many different shapes.

This simple but insightful puzzle can be solved in under 7 seconds if only you know well enough about triangles ⏳

Personally I solved it in 3 seconds when I first saw it 🙂

Here’s a hint: move them around and M and N are the midpoints…

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Once again, this is a good moment to pause the article and give the problem a go yourself. When you’re ready, keep reading for the solution. And if you come up with your own approach, feel free to share it in the comments — I’d love to see how you tackled it.

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Solution

In case you missed it, M and N are the midpoints of the size of the rectangle. Let’s jump into the heart of the solution with this diagram.

All the blue triangles are now above the line MN. We can see that the triangles is half the area of the rectangle LKNM.

Rectangle LKNM is half of the whole rectangle.

And half of half is just (1/2)(1/2) = 1/4 🧁

And we are done! Did you solve it in 6 or 7 seconds?

And that’s our answer. How amazing. Hey, don’t forget to clap👏 the article as a token of appreciation. Thank you 🦁