Viral problem · Decoded
The PEMDAS Truce
A century of typesetting choices crashed into a Casio in 1996. Here is the actual ceasefire on the most-argued-about expression on the internet, with primary sources, calculator screenshots, and a verdict.
Quick answer
Both 1 and 9 are defensible answers to 6÷2(1+2). The expression is genuinely ambiguous. Modern calculators, modern typesetters, and modern mathematicians would all rewrite it as either $\frac{6}{2(1+2)}$ or $\frac{6}{2}\cdot(1+2)$, and never publish it the original way. The result you get depends on whether you read 2(1+2) as a single packaged term (multiplication by juxtaposition, gives 1) or as two separate steps (explicit multiplication, gives 9). Each convention has a respectable century of history behind it. Neither is wrong. The expression is.
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