India, April 13 -- Brain teasers have long been a favourite among puzzle enthusiasts online, offering a quick mental workout and a sense of satisfaction when cracked. Particularly, number puzzles tend to go viral, as they challenge logic and observation in equal measure. And if you enjoy the thrill of decoding patterns, a new puzzle making the rounds on social media might be just the brain workout you're looking for.

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Shared by the X account Brainy Quiz, this teaser features a 3x3 grid filled with numbers. The top row reads 4, 9, 2; the middle row has 3, 5, 7; and the bottom row shows 8, 1, with the third number left as a question mark. User...