Twitter Can't Agree On How To Solve This Deceptively Simple-Looking Equation

Mason Joseph Zimmer

If you took a poll on everyone's least favorite subject to study in school, it wouldn't be terribly surprising to see math near the top.

And sure, there would be a significant number of people who would tell you that they'd much rather take math than English. After all, how we fare in English and other arts-based curriculum can depend on the perspective of a given teacher, whereas your answer is either right or wrong in math.

But whether it was due to the repetitive homework or how easily one can get lost in all the rules of math, it remains true that the fastest way to intimidate a large section of the population is to get them to solve an equation.

And today, Twitter was faced with one that combines the detail-sensitivity of math with the interpretive requirements of English. Perhaps that's why nobody can seem to agree on how to answer it.

One afternoon this week saw Twitter user @lesvity take to Twitter with what looks like a fairly simple equation.

And other than the original call to solve it, all we knew was that this person got an answer of seven when they did it and couldn't fathom why so many others didn't.

And I suppose their confusion makes sense because almost everyone who replied was just as puzzled as to how they ended up with seven.

After all, whether they used the mnemonic PEMDAS or BODMAS to figure out the order of operations, most commenters knew that you had to solve the portion of the question in the parentheses first.

However, this seemed to be the only fact of the question that everybody actually could agree on.

Because once they explained that step, users would go on to state that the answer was either one or nine with the same level of confidence.

In both cases, users were only diligently applying what they were taught.

For those who landed on the number nine as an answer, they're working under the assumption that all division and multiplication should happen from left to right.

So while they start by adding the one and the two in the parentheses together, they then proceed to divide instead of multiplying that new sum by the number next to it.

Therefore, they see the question as asking them to divide six by two, which they then multiply by the remaining three in the parentheses.

Since three times three is nine, that's how they arrive at that number.

Meanwhile, those who arrived at one as their answer are sticking closer to the order laid out in PEMDAS.

For them, the idea of going from left to right happens much later in the equation than it did for those who got nine as an answer.

After resolving the parentheses, they then multiply the sum of three by the two positioned next to it since multiplication comes before division in PEMDAS.

Since this leaves them with six, they then see the question as ultimately asking them to divide six by six. Obviously, this gets them an answer of one.

Once that point of contention was cleared up, Twitter user @Froman_Official was even able to figure out how that first person ended up with seven.

Rather than resolving the sum in the parentheses as those who answered one or nine did, it seems that @lesvity and anyone who answered like them instead multiplied the two next to the parentheses by both numbers inside of it.

This leaves them with an equation that divides six by two before adding four. This way of working out the equation doesn't involve PEMDAS at all, but it explains how they arrived at seven.

So now that we know how everyone came to their answers, what's the real answer?

And according to Australian mathematician and comedian Matt Parker, the answer is that the question needs to be written better because it's too ambiguous.

After all, we've demonstrated by now that the question is potentially asking people to do two completely different things.

That said, the answer that Parker arrived at was nine because he said PEMDAS is a convention to make equations more clear rather than a hard and fast law for solving them.

So to avoid the very confusion we're discussing today, he would've written the question as "6 ÷ 2 x (1+2)."

But of course, that wouldn't leave any room for a Twitter debate that people get much more personally invested in than they need to.