Here’s the visual for an excellent math problem by FiveTriangles that Dylan Kane introduced to the MTBoS. I had noticed some conversation about it on Twitter, so I thought I should give it a try. The prompt is: What proportion of area of the three congruent equilateral triangles is shaded?

I don’t want to give away any answers or methods, but I will say that this is a really nice problem. I did the things that were obvious to me at first, but then I got a little stuck. So then I got a bit flustered. “I have a math degree- this should take me ten seconds,” I irrationally thought to myself. I tried some stupid things that I knew weren’t going to help me, and after that I had to go take care of something else, so I left my pencil and paper on the table and didn’t think about those triangles again until later that day. When I returned to the problem, something suddenly clicked, and I was able to quickly move forward and solve the problem. Funny how that works.

It was super fun to do some math just for the heck of it. I should do more of that.

I would definitely recommend giving this one a try, but please, no spoilers! Don’t comment with your answer. Email me or tweet me if you want to exchange solutions.

Enjoy!