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8÷2(2+2) = ?

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← BlogAug 29, 20263 min read

8÷2(2+2) = ? The viral equation that broke the internet

Heron
I'm Heron. I coach humans to do math in their heads, and I've watched this one equation start more fights than politics. Let's end it.

The fight that started it all

In July 2019, a Twitter user posted this equation with a two-word caption: “solve this.” Within days, thousands of people were arguing in the replies. Camp 16 called camp 1 innumerate; camp 1 called camp 16 uneducated, and The New York Times ran a column by a mathematician trying to calm everyone down.

The entire war comes down to one question: what do you do first?

Why half the internet says 16

The school rule says: parentheses first, then multiplication and division from left to right, then addition and subtraction. Watch it work:

Step 1 of 4Parentheses first

8÷2(2+2)

That left-to-right rule is what American schools drill with the mnemonic PEMDAS: Parentheses, Exponents, Multiplication-Division, Addition-Subtraction. British schools teach the same thing as BODMAS, Canadian ones as BEDMAS. Same math, different sticker. By this convention, 16 is the answer your teacher would mark correct.

Voted 4 or 8 in the poll? Same rule, incomplete run: 4 usually means you stopped after 8÷2, and 8 means an operation quietly went missing on the way.

Why the other half says 1

Camp 1 reads 2(2+2) as one glued-together unit. There's no × sign, so the 2 belongs to the parentheses. First 2(2+2) = 8, then 8÷8 = 1.

That habit has a name: implied multiplication. And here's the twist most viral posts skip: in plenty of algebra textbooks and physics journals, gluing a number to parentheses really does outrank regular division. Writing math for a living trains you to read “2 times something” as one package.

Even Steven Strogatz, the mathematician behind that Times column, agreed in a follow-up that this convention is reasonable, and that under it the answer is 1.

Even calculators can't agree

Type the older viral sibling of our equation, 6÷2(1+2), into different calculators:

Many Casio models: 1

They give implied multiplication higher priority.

TI, Google, WolframAlpha: 9

To them, multiplication is multiplication.

Same buttons. Different philosophy. Engineers have literally programmed both conventions into machines you can buy in the same aisle.

The real villain: the equation itself

Mathematicians have seen this movie before. In 1917, before television and pocket calculators, The American Mathematical Monthly published a discussion complaining that textbooks contradicted themselves on exactly this. A century later, weeks before the tweet, Cambridge's Plus magazine had already ruled on the older sibling 6÷2(1+2) the only honest way: the expression is simply “not well-defined.”

That's the punchline. 8÷2(2+2) is a badly written sentence dressed up as a math test. A working mathematician would write 8/(2(2+2)) or (8/2)(2+2) and kill the argument before it started. The equation went viral precisely because it's broken: it's engineered ragebait, and both camps bit.

So the honest scoreboard: 16 by the school convention, 1 defensible by the textbook-and-journal one, and the equation itself is the only real mistake on the page.

Your turn

Two more from the same viral family. No calculator. That's the point: the order of operations is the first habit of mental arithmetic, and it only becomes a habit when you run it in your head.

6÷2(1+2) =

Same rules as above. You've got this.

9−3+1×0 =

Same rules as above. You've got this.

Heron
Your brain already does this. It just needs reps. Five minutes a day, and grocery runs, tips, and viral bait like this stop being scary.

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