India, Aug. 10 -- Brain teasers have long been enjoyed as a playful yet effective way to keep the mind sharp. They push people to think outside the box and even ignite friendly debates. Now, a new puzzle making the rounds on Facebook is doing just that, leaving users both entertained and baffled.

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The challenge, shared by Facebook user Arshdeep Soni, features a rectangular image divided into vertical sections, with a single diagonal line running from the top left to the bottom right corner. At first glance, it looks simple. But the real task is far from straightforward: count every possible triangle within the diagram. That means sp...