But the correct answer is 25. The 25th triangle is hidden in the 'A' in the artist's signature. Though Quora user Yu Min Tan said there was another triangle in the image if you count the word 'triangles'. read more
We get six triangles from the upper half, six more considering bottom base as base of triangles and six considering the diagonal line as one of the sides. Lastly, we get six more triangles taking into consideration the diagonal line and the top vertex So, the final answer according to me should be 24. read more