Overview
- Viral mental‑math puzzles circulated on social media and were republished by mainstream outlets, with Diario Uno publishing (15 x 3 + 9) ÷ (4 + 5) and LA NACION publishing 2 + 4 x (3 x 5) – 3.
- Diario Uno’s June 2 piece shows the first puzzle solved by applying PEMDAS to give 6 and LA NACION’s June 3 article uses PEMDAS to show the second puzzle equals 59.
- LA NACION presented a performance claim that 70% of people cannot solve its puzzle in under 30 seconds but did not provide primary data or a clear source for that statistic.
- Both outlets link the puzzles to neuroscience research—Diario Uno cites Dr. Yaakov Stern on cognitive reserve and LA NACION cites a Princeton/Journal of Neuroscience study—but both summaries simplify the original research and do not fully document sources.
- Readers should note the difference between these simple order‑of‑operations demonstrations, which teach PEMDAS (parentheses, exponents, multiplication/division left to right, addition/subtraction left to right), and the more complex, longer‑term findings of the neuroscience literature on cognitive training.