A seemingly simple math problem appears to have stumped every single person on the internet, breaking brains and calculators in the process.
The math problem was first tweeted out in summer 2019, with the request for “one of my mutual friends solve this.”
But this week the problem found new people to drive up a wall.
The equation is fairly straightforward at the start. But exactly how you solve the problem is not proving to be so direct.
oomfies solve this pic.twitter.com/0RO5zTJjKk
— ❦ (@pjmdolI) July 28, 2019
Math equations are solved in a specific order of operations, which is taught as PEMDAS. That acronym stands for Parentheses, Exponents, Multiplication, Division, Addition, and Subtraction.
In American schools, children are taught to remember this with the phrase Please Excuse My Dear Aunt Sally.
But apparently that doesn’t stick, because almost no one could figure out the problem’s real answer. It’s either 1 or 16, according to most replies - but those are very different numbers.
The correct answer is that it’s both 1 AND 16, because the only guide to mathematical operation is convention & verification by others, and order of operations is a specifically context sensitive & variable thing, which here is purposefully represented poorly. https://t.co/eQGvj5nt4f
— The Cosmist Insurrection, Inc. ™ (@yungneocon) August 21, 2020
“I do parenthesis, multiplication, then division so i believe it’s 1,” wrote the original tweeter. “See so apparently division comes first......this is why I didn’t do well in math okay.”
I've been thinking about this old problem at least once a week for the past 2 years, and every time I do it ruins my day and I turn hostile for the next 12 hours. https://t.co/VTVEjd6kuZ
— Holden Milne (@holdenmilne2) June 14, 2021
People on the app chimed in to help, usually with quite a bit of patience.
This surprises people! It's really valuable, though, for J's domain: mathematics on multidimensional arrays. You know the precedence of 2*3+4, but what about 2⍟3⌽4? We don't have an intuition for what that should be! Better to drop precedence entirelyhttps://t.co/WHB4r8ctET
— Hillel (@hillelogram) April 22, 2021
“With my degrees I would say you were correct but there’s something you’re missing,” wrote one mathematician in 2020. “The ‘P.’ Parentheses are done first, including the multiplication of numbers attached. The way you did is also correct with current mathematics being taught incorrectly for years. #AmericanSchools”
division signs fucking suck, cause unique notational difficulties and stop you using useful spacial metaphors which help teaching the actual operation. they shouldn't ever be used. ever. https://t.co/B5rikYKn62
— michael 🪐 (@regresssion) August 21, 2020
“I have 2 math degrees,” another user replied. “It’s 1.”
Whether or not the answer is in fact 1, however, got so heated with the original tweet that the New York Times asked wrote mathematician and Cornell professor Steven Strogratz to tackle it.
“Deal with whatever is in parentheses first. Of course, 2+2 = 4. So the question boils down to 8÷2×4,” Strogatz wrote in 2019. “And there’s the rub.”
First: as others (@JoelBSperanza @meaganrodda) have pointed out, the goal is understanding. Many use these acronyms to find answers without real understanding, which is the opposite of what maths is really about. It’s why this problem confused so many. 2/n https://t.co/y88BkYyWPr
— Eddie Woo (@misterwootube) May 9, 2020
“Now that we’re faced with a division and a multiplication, which one takes priority?” the Times asked. “If we carry out the division first, we get 4×4 = 16; if we carry out the multiplication first, we get 8÷8 = 1.”
Strogatz, who previously complained on Twitter that order of operations never actually came up, had no real conclusion.
It’s amazing to me how much time and effort goes into arguments about ambiguous PEMDAS expressions. In real math this never comes up.
— Steven Strogatz (@stevenstrogatz) August 30, 2018
The person writing this story, meanwhile, has not done a math problem since roughly 2008, and has literally no idea what any of this means. In her opinion, the answer is like, negative 27, just because that sounds like a cool number.
