The internet is brimming with puzzles and debates, sparking curiosity and sometimes confusion over what the correct answer might be. A great example is the famous “blue and black dress” debate that swept through social media and even stumped experts. A similar phenomenon took place with a viral math problem that caused significant controversy across the web, involving everyone from everyday social media users to scientists who tried to crack the code.
In 2019, a Twitter user posted a seemingly simple math equation, asking followers to solve the now-infamous problem: 8 ÷ 2(2 + 2). This math puzzle ignited widespread debate, not only on Twitter but across various social media platforms. People were stumped and divided over the solution, with each camp passionately defending their answer.
Even the editors at Popular Mechanics, a well-known lifestyle magazine, couldn’t reach a consensus and ended up taking the debate to their workplace chat. Heated discussions emerged as they attempted to decode the problem and agree on a solution. The confusion centered around the order of operations, commonly taught using the acronym “PEMDAS” (Parentheses, Exponents, Multiplication, Division, Addition, and Subtraction). This rule, a cornerstone of elementary and high school math education, indicates the order in which operations should be solved. Following PEMDAS, problems must be addressed in the order of parentheses first, then exponents, followed by multiplication and division, and finally addition and subtraction from left to right.
One group of editors, relying on traditional interpretation, argued that solving 2 + 2 within the parentheses should come first, yielding 4. This approach simplifies the equation to 8 ÷ 2 x 4. According to PEMDAS, the rule suggests moving from left to right once the parentheses are solved. This leads to 8 ÷ 2, which results in 4, and then multiplying by 4 gives a final answer of 16.
However, not everyone agreed with this interpretation, and the debate continued to gain traction. Many online, including some mathematicians, argued that the answer was actually 1, proposing an alternative approach. These critics believed that while the parentheses should be solved first, the sum (4) should remain linked to the multiplication directly following it. This would simplify the problem to 8 ÷ 2(4), which they argue should be read as 8 ÷ (2 x 4). Using this approach, they reached a different solution. Following the multiplication, 2 x 4 equals 8, and 8 ÷ 8 results in 1.
The split within Popular Mechanics was reflective of the broader public opinion, with mathematicians weighing in to clarify. Mike Breen, from the American Mathematical Society Public Awareness Office, explained that while, according to the order of operations, 16 would typically be the correct answer, the way the equation was written left room for interpretation. Breen acknowledged that, “In math, a lot of times, there are ambiguities. Mathematicians try to make rules as precise as possible. According to the strict order of operations, you’d get 16, but I wouldn’t hit someone on the wrist with a ruler if they said 1.”
Despite this, many were left unconvinced. Some individuals within the Popular Mechanics team sought further insight from Rhett Allain, a Physics Professor at Southeastern Louisiana University. Professor Allain provided additional clarity by explaining that this problem was as much about convention as it was about the rules of math. “This is convention. We have conventions on how to write these things, just like we have conventions on how to spell stuff. But still, there are different conventions. Some people spell it as ‘gray’ and others as ‘grey.’ We still understand what’s going on,” he noted.
To settle the debate, Allain suggested that the equation might have been better written as *8/(2(2+2))**, which would yield 1 as the final answer. This alternate form of notation clarifies the intent by reducing ambiguity, making it easier to see that 2 x 4 should be completed before dividing into 8.
In the end, this viral math problem highlighted how even the simplest expressions can lead to significant debate when people interpret conventions differently. As the math world discovered, a seemingly straightforward problem can spark a whirlwind of confusion, uniting people in their love (and occasional frustration) with numbers.
