Fri, 8 Mar, 2019
Maths hack goes viral and blows people’s minds: "You've changed my life"
A UK copywriter has shared an arithmetic trick that makes calculating a lot easier.
Ben Stephens took to Twitter to share his “fascinating little life hack” for doing percentage calculations.
He showed that by flipping numbers and multiplying them as per usual will result in the sum you are looking for.
“So, for example, if you needed to work out 4 per cent of 75 in your head, just flip it and and do 75 per cent of 4, which is easier,” Stephens wrote.
Fascinating little life hack, for doing percentages:
x% of y = y% of x
So, for example, if you needed to work out 4% of 75 in your head, just flip it and and do 75% of 4, which is easier.
— Ben Stephens (@stephens_ben) 3 March 2019
People on the Internet have been amazed by the simple maths hack, with Stephens’ post accumulating more than 4,000 retweets and 11,000 likes at the time of writing.
“You’ve changed my life,” a man simply replied.
Another man commented that he was “furious” for not knowing this sooner. “I'm 30 and have avoided knowing this until some hero on Twitter tweeted it.”
One wrote, “How could maths teachers let us live without this!”
The tweet also inspired some teachers who had not been aware of the switching technique.
“I teach Maths at primary level and had never realised this,” one wrote. “50 per cent blown away/50 per cent going DOH!”
A woman chimed in, “I used to teach maths for reporters as a part of journalism school and wish I’d had this explanation in my back pocket. I had other tricks for mathsphobes but this is far more elegant.”
Some complained that the trick is a simple mathematics rule rather than some little-known hack.
“Do you really think people don’t understand such a simple concept enough to know this? Good grief,” one wrote.
“Those of us who studied basic arithmetic at school are scratching our heads as to why this is a revelation,” another added. “Next you’ll be telling us that x+y = y+x and that xy = yx.”
Stephens defended his post, saying it was meant as a way to pique people’s interest in numbers. He admitted that he also just learned about the ‘switcheroo’ fact.
“I almost think stuff like this would be lost on a kid at school,” he wrote. “It has way more impact a couple of decades later when you see it and you're like OMG IT WAS SITTING RIGHT THERE THE WHOLE TIME.”
Did you know this maths trick? Let us know in the comments.