Turns out Everyone Solves Simple Math Problems In Their Head in Different Ways

"What happens in your head when you do 27 + 89?" That was the simple question asked by one Twitter user, the simple question that launched a fascinating thread. I say this as someone who actively tries to avoid doing math whenever humanly possible. I was fascinated by this Twitter thread.

Turns out there are so many different ways to solve simple math problems in your head. People's brains work completely differently. Some of it also has to do with the way you're taught. So first, before we explore other people's answers, think about your own.

Here's what happens in mine: I know that 7 + 9 is 16. It was engrained in my brain in elementary school thanks to countless worksheets and quizzes. I have 7 + 9 memorized. 

So, once I have sixteen, my mind becomes a piece of paper. I write down the 6 and carry the one, and add 1 + 2 + 8. I know 2 + 8 is 10. Then I add 1 and get 11. And that's how I know that 27 + 89 is 116. I don't know if it's the most efficient way to solve this problem. It's the way I was taught, and it's what happens in my head when I'm asked to solve it.

Now, at least one person had a similar answer. But I expected this to be the way most people solve this problem. And wow, I was wrong. I was so very wrong. There are so many other processes that people go through in their heads to arrive at the correct answer. And I never would have thought to do any of them!

Sabrina and I are on the same page. I don't know if I'm showing my age here, but back in the early to mid-'90s, that's how they taught kids to solve these sorts of problems. And the method has stuck with me ever since, probably partly because I have no natural inclination to think about numbers in unconventional ways. 

But plenty of people do. And that, combined with the fact that teaching methods have changed over the years, have led to some seriously creative and different ways that people automatically turn to in order to solve a problem like 27 + 89. 

While these totally make sense, they are just simply not where my mind goes when I see a problem like this. It's fascinating to learn that people's minds automatically solve problems so differently. 

I don't know if one way is "better" or quicker than any other. We all arrive at the same answer. It's just about how people's minds work and how they were taught. Some of these methods are not only simple and easy to follow, but they also seem quite efficient! 

But this one, this does not work for me. Rounding up both numbers? And then having to remember how much you rounded each number up and adding those together to subtract from the total?! 

It's bonkers to me that this is where this person's mind goes in order to solve this problem, but maybe I'm the weird one! Maybe this makes sense to everybody else.

Did you see your method listed here? Do you have yet another way that your brain chooses to solve this problem in your head? All this made me realize is that when I have kids, I'm going to seem like a real old person when I try to help them with their math homework. Yikes!