How Many Triangles Do You See in This Puzzle?

How many triangles are there?

Calling all brain teaser aficionados: This triangle trick (and no, it’s not an optical illusion) is sure to baffle even the most astute of brains for at least a few minutes.

Kumar Ankit, an engineering student from India, designed and posted this geometric puzzle to Quora, challenging users to find all the hidden triangles in this image (nothing goes super-viral like a controversial shape). You’re going to have to really exercise that eye for detail (and a thorough concept of geometry) to solve this visual riddle. Don’t get discouraged if you’re more right-brained than left—these visual brain teasers and rebus puzzles are probably right up your alley. If picture puzzles are more of your thing, see if you can find the hidden objects in these pictures.

How Many Triangles Do You See?

The-Internet-Can't-Figure-Out-How-Many-Triangles-There-Are-in-This-ImageTatiana Ayazo /Rd.com

The answer is lucky number 24—25 if you want to get fussy.

At first glance, the image seems to be a simple illustration with multiple shapes. Now here’s the catch—count how many triangles are in the drawing. People are scratching their heads at the different numbers they are coming up with (something similar happens with this viral duck riddle).

If you’re completely stumped, we’ll give you a hint: The trick lies in factoring multiple smaller triangles into becoming a bigger triangle.

Got an answer? If you did the math and your answer was 24, congratulations, you’re in the majority. Most people on Quora agreed that the answer is 24, with each row containing six triangles. If you’re into shapes, also try to figure out how many squares are in this image.

However, if you really want to get technical, the truly “correct” answer is 25. The 25th triangle is hidden in the “A” in the artist’s signature in the right-hand corner. An even more nitpicking Quora user noted there was another triangle in the image if you count the word “triangles.” Less than 1% of people can ace this shapes brainteaser (though we bet the aforementioned eagle-eyed user is among that statistic).

Math expert Martin Silvertant posted a very helpful graphic on the site walking through how to locate the pictorial triangles and provided a logical explanation as to how you can stretch the number to 26 of them. “A triangle is a mathematical idea rather than something real; physical triangles are by definition not geometrically perfect, but approximations of triangles. In other words, both the pictorial triangles and the words referring to triangles are referents to the concept of a triangle,” said Silvertant. If that was way too easy for you to figure out, these logic puzzles will keep you guessing.

If you’re really getting into the debate and want to hash out (or defend) your answer, check out the entire Quora discussion for different users’ mathematical methods—and then check out these math puzzles for more brain busters. If you’re up for another challenge, try these brain teasers that will leave you stumped.

Hana Hong
Hana Hong is a journalist/storyteller who writes for Reader's Digest, InStyle, CollegeFashionista, Her Campus and The Fashion Network, among other publications. She hails from the Midwest, where she graduated from the University of Illinois with a BA in News-Editorial Journalism, but has a passion for the East Coast.