A simple math problem has divided the internet

Story by CBC Kids News • 2019-07-31 17:08

Math: It's what's fire this week

Math can be fun, but it can also be tricky.

Adding, subtracting, multiplying and dividing — numbers can really boggle the mind sometimes.

And really, this is true at any age, with a lot of opinions circulating on the internet this week about the answer to this math problem:

A twitter user asked a simple third grade math equation

A Twitter user named @pjmdoll posted the equation 8 ÷ 2(2 + 2) = ?

The answer is … not immediately clear, given the variety of answers.

Many on Twitter were absolutely confident the answer is one.

Someone on Twitter with two math degrees said confidently that the answer is one

And many were confident that the answer is 16.

Another Twitter user confidently said the answer is 16

Others were confident that the answer is both.

Another Twitter user confidently said the answer could be both

But generally, many were reminded why they don't like math.

Another Twitter user said this equation reminded them why they daydreamed through math class

But what is the true answer, especially if two different calculators have two different outcomes?

Another Twitter user tried the equation on two different calculators and got two different answers

It really comes down to your approach to math when you're required to perform an order of operations.

In Canada, BEDMAS is taught, which means that anything in brackets is handled first, followed by exponents, division or multiplication (working left to right) and finally, addition or subtraction (again, working left to right).

Another Twitter user brought up how they used BEDMAS to get the answer 16

That would mean you'd add inside the brackets first (2 + 2), for a result of four.

step 1: 8 ÷ 2 (4) = ?

That leaves you with 8 ÷ 2 (4) = ?

Working left to right now, you have to take care of the division first, as 2 (4) is a multiplication operation — and not some stray bracket work.

step 2: 4(4)=?

Eight divided by two gives you four, which means your equation would now look like this: 4 (4) = ?

step 3: 4(4)=16

Now all you have to do is multiply the two numbers, giving you a total of 16.

So why are people getting the result of one? Well, it appears to have something to do with an order of operations called PEMDAS.

This method asks people to do parentheses (brackets) first, followed by exponents, multiplication or division, and then addition or subtraction.

But here's where it goes a bit sideways: PEMDAS still requires you to do your division/multiplication and adding/subtracting from left to right.

So the outcome should be the same: 16.

But if you were to multiply first, as some have, the answer becomes one.

step 1: 8 ÷ 2 (4) = ? step 2: 8÷ 8=1

Math is tricky!

What's Fire This Week is your weekly digest of what everyone's talking about.

Get your class on the same page, add this to
Google Classroom

Was this story worth reading?