It sounds like it could be from a school geometry class, but it's a puzzle. Finding the right number of triangles in this drawing may seem easy, but if you start thinking about it, you’ll realise that there could be more than you think.

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It is likely that you are mistaken the first time you think you’ve solved the problem. Someone simply drew a triangle with several diagonal and horizontal lines separating this large triangle into several triangles.

Do you want to know the answer? If so, keep reading, if not, stop here, take a few minutes to think, and come back to read on.

There are several ways to figure out how many triangles there are. You can count them one by one throughout the big triangle, or you may notice that there are six triangles per row. So if you multiply six by the number of rows (four), the result is twenty-four.

The drawing has something written on it however, the question ‘How many triangles?’ The signature bears the name Amy, and the A has another triangle in it. So is the total 25 triangles? Many don't agree and think the signature doesn't count. What do you think?