India, May 2 -- Brain teasers are a fun and fascinating way to challenge our minds, testing our problem-solving skills and keeping our brains sharp. Maths brain teasers, in particular, are a favourite for many, offering an engaging way to test numerical thinking. But sometimes, these puzzles can be tricky enough to leave even the most logical minds stumped. If you're a fan of maths brain teasers, then the latest puzzle shared on X (formerly Twitter) is sure to leave you scratching your head.

(Also read: IQ test: You're a genius-level problem-solver if you can crack this tricky number puzzle)

Shared by the account Brainy Quiz, the teaser reads:

"Only Geniuses, if 2 = 6, 3 = 12, 4 = 20, 5 = 30, 6 = 42, Then 9 = ?, Fail: 98%"

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