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Watch this 11-minute mathematical puzzle video that presents a deceptively simple brain-teaser known to stump many US college students. Tackle a Harvard entrance exam style problem that tests your logic, reasoning, and algebraic skills through a classic "working together" word problem. Follow along as the presenter first demonstrates a common error that students make at the 0:57 mark, then reveals the correct solution methodology at 3:34. Challenge yourself with this interview question format that serves as both a genius test and IQ puzzle, perfect for sharpening your mathematical reasoning abilities and understanding why seemingly straightforward problems can trip up even advanced students.
