A simple math problem shared online in 2019 sparked one of the internet’s biggest debates, with thousands arguing over whether the correct answer was 1 or 16. The equation— 8 ÷ 2(2 + 2) —quickly went viral as people applied different interpretations of the order of operations.

Those who answered 16 followed the standard PEMDAS/BODMAS convention. First, they solved the expression inside the parentheses, turning the equation into 8 ÷ 2 × 4. Since multiplication and division have equal priority, they worked from left to right: 8 ÷ 2 = 4, then 4 × 4 = 16.

Others argued the answer should be 1, treating 2(4) as a single grouped expression after solving the parentheses. That interpretation effectively becomes 8 ÷ (2 × 4), resulting in 8 ÷ 8 = 1. Some mathematicians noted that the equation’s formatting is ambiguous, making both interpretations understandable depending on the convention being used.

Most mathematics educators agree the expression is poorly written and should be rewritten with clearer parentheses to avoid confusion. Under the standard left-to-right order of operations taught in most schools today, 16 is generally considered the correct answer. The debate serves as a reminder that clear mathematical notation is just as important as the calculation itself.