Sarah Biren
Sarah Biren
February 8, 2024 ·  2 min read

It May Look Too Easy At First, But Don’t Be So Quick To Judge. A Lot of Adults Are Flunking This Equation

Math is super fun. You just have to tell yourself that if someone else could solve this, you can too. Even if you don’t get the answer correctly at first, you’ll have a swell time seeking the solution.

It’s important to take a swing at a random math question once in a while. It’s beneficial to your brain if you can do that at least one every day. Exercising the brain regularly is thought to prevent the usual decline in cognitive performance that comes with old age and dementia [1]. Math comes in degrees of difficulty, so don’t fret.

The equation below might seem like something a 5th grader could solve, but don’t get too confident. Those math skills you once learned may have faded. Besides, you either ‘use it or lose it.’ Many adults have even been floored (and humbled) by this one.

Take a second thought

If your day job doesn’t include constant use of mathematics (like most of us), you may need some reminders, because there are still a few lessons to learn from this equation (all the accountants, rocket scientists, and physicists can stop listening now). Equations like this one are not only to test our knowledge of math and give our brains a workout but to instill some important life lessons in us.

This particular one tells us to not be too quick and jump to conclusions. Don’t always rush in head first without scanning the possibilities and obstacles, and laying out a sensible course of action. Without further ado, here’s the answer, as simple as it may have seemed.

3 + 3 x 3 – 3 + 3 = 12

Initially many may have arrived at the answer of 18. Which logically, can make sense.

Looking at it, it seemed simple.

3 + 3 = 6

6 x 3 = 18

18 – 3 = 15

15 + 3 = 18

Some may have tried solving it in their heads, and it would seem absolutely correct. The only thing upsetting part would be, their answer wasn’t 12 (if it was, good on you).

Sorry, but 18, or any other number other than 12 is not the answer. Why? The answer lies in the order of operation. Solving the expression straight from left to right is a no-no. There’s a reason the basic set of rules in algebra known as BEDMAS or PEDMAS (Brackets/Parentheses, Exponents, Division, Multiplication, Addition, Subtraction) is in place.

With that in mind, let’s explain how we arrived at the answer.
Multiplication precedes addition and subtraction on the priority level, so you have to perform 3 x 3 first, which equals 9.

9 + 3 = 6.

Addition and subtraction are of the same priority, so anyone can come before the other.

12 – 3 = 9.

9 + 3 = 12.

There you go. That’s how you get the answer, 12. Math is cool, right? You may remember learning this in grade school and regardless of if you got this right, now you have. It’s always good to stay sharp.


  1. 6 simple steps to keep your mind sharp at any age. Admin. Harvard Health Publishing. Retrieved from No date available.