Simple Equation That Stumped 40% Of Japan's Young Adults Goes Viral

I think it's fair to say that, growing up, math wasn't the favorite subject for many of us. In my case, that was partially because math class always seemed to have the most homework and because that work struck me as boring and repetitive.

So, like many who aren't in school anymore, I've noticed a significant atrophy in my math skills that likely would have embarrassed the high school version of myself. And that atrophy was the subject of some concern in Japan as the way 20-somethings there tended to answer one simple question differed significantly from how they did 30-40 years ago.

A 2014 study published by the Central Japan Economic Federation included a brief math problem in an overall assessment of educational performance over the last 40 years.

And while it's hard to get a sense of the study's findings if you don't understand Japanese, Sora News 24 reported that only 60% of Japanese adults between the ages of 20 and 30 were able to correctly solve it.

On its own, that number isn't particularly meaningful, but it likely seems a little startling when compared to the success rate from the 1980s.

According to Sora News 24, 90% of people in the same age group were able to get it right back then.

Naturally, this left people wondering what has brought about this decline and it turns out that the best way to get the answer is to run through the problem yourself.

And we were given an opportunity to do that when a YouTube channel called MindYourDecisions released a video walking through it back in 2016.

But before we get into how this question works and what it means, just take a moment to determine the first answer you get after a quick once-over of the equation.

If your answer was three, then I'm afraid I'll have to unearth a term that you probably got sick of hearing back in school.

And that term is PEMDAS! If you landed on three, that means you subtracted three from nine before you took care of the division part of this equation and that reminds us as to why we have the order of operations that we do.

However, this wasn't the error that befell most of the 40% of Japanese young adults who answered incorrectly, because they came up with nine.

Those of you who cheated and entered the equation into Google's calendar might be looking a little confused now. Nonetheless, both Google and the members of that 40% turned out to be wrong and it apparently has to do with the way we read numbers nowadays.

After all, we read that one part of the equation as "three divided by one third," right?

Well, that's apparently not how they would have seen that 30 years before the study was conducted.

As we can see in MindYourDecisions' rundown here, that fraction would have just signaled to people that they need to divide in the place shown there. This would have them reading that part of the equation as "three divided by one divided by three."

Since this number turns out to be the same as multiplying the first "three" by the reciprocal of that "fraction," we end up multiplying three by three instead.

That gives us nine and in the end, we're subtracting that nine in the equation from the first nine we see in the equation and adding one.

Since the two nines cancel each other out, that leaves us with an answer of one.

h/t: YouTube | MindYourDecisions, Sora News 24

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