If you’re anything like me, you might feel a sense of relief knowing the last time you had to wrestle with a tricky math problem or dive into algebra was back in high school. Math has never been my strongest suit, and while I know some people genuinely enjoy it, I’ve always gravitated more toward creative pursuits. But hey, we all have our unique strengths, right?

That said, while I didn’t particularly enjoy solving math problems in a noisy classroom filled with restless students, I’ve surprisingly developed a fondness for tackling online math challenges. These puzzles and riddles allow me to take my time, work at my own pace, and even have a little fun along the way. It turns out, solving these brain-teasers can be quite satisfying.

And I’m not the only one who feels this way! There’s a whole community of people who relish the opportunity to recognize patterns, tackle logic puzzles, and solve math challenges. With that in mind, we thought it would be exciting to bring a fun and brain-stimulating math problem to our amazing readers. Are you ready to put your thinking cap on and test your problem-solving skills? If so, we’ve got just the challenge for you!

Take a look at this intriguing problem that has left many scratching their heads online. Here it is:

If 1 + 4 = 5, 2 + 5 = 12, and 3 + 6 = 21, then what is the value of 5 + 8?

To make it easier, here’s how it’s written out:

1 + 4 = 5
2 + 5 = 12
3 + 6 = 21
5 + 8 = ?

At first glance, this problem seems straightforward. However, the more you think about it, the more puzzling it becomes. It’s no wonder people online are so divided about the correct solution. The key lies in your approach—how you interpret the problem and the method you choose to solve it can greatly affect the outcome.

So, what’s the bottom line? There isn’t just one “correct” answer! In fact, this puzzle has several valid solutions, each derived using different logical approaches. If you’ve already attempted to solve it, or if you found it so frustrating that you’re now eager to see the solutions, let’s dive into five unique strategies for tackling this tricky problem.

Solution One
1 + 4 = 5
2 + 5 = 2 + 2(5) = 12
3 + 6 = 3 + 3(6) = 21
5 + 8 = 5 + 5(8) = 45
Algorithm: $A+A(B)=C$
Answer: 45

Solution Two
1 + 4 = 1 + 4 + (0) = 5
2 + 5 = 2 + 5 + (5) = 12
3 + 6 = 3 + 6 + (12) = 21
5 + 8 = 5 + 8 + (21) = 34
Algorithm: A+B+C′=CA + B + C’ = CA+B+C′=C, where C′C’C′ is the previous answer
Answer: 34

Solution Three
1 + 4 = 5
2 + 5 = (5 + 2) + (5) = 12
3 + 6 = (7 + 2) + (12) = 21
5 + 8 = (9 + 2) + (21) = 32
Algorithm: For X=5,C=X+C′,X=X+2X=5, C = X + C’ , X = X+2X=5,C=X+C′,X=X+2, where C′C’C′ is the previous answer
Answer: 32

Solution Four
1 + 4 = 5
2 + 5 = 7 (base 5) = 12
3 + 6 = 9 (base 4) = 21
5 + 8 = 13 (base 3) = 111
Algorithm: For X=6,C=(A+B)(10→X),X−1X=6, C = (A + B)^{(10 \to X)}, X – 1X=6,C=(A+B)(10→X),X−1
Answer: 111

Solution Five
1 + 4 = 5
2 + 5 = 7 (base 5) = 12
3 + 6 = 9 (base 4) = 21
4 + 7 = 11 (base 3) = 102
5 + 8 = 13 (base 2) (binary) = 1101
Algorithm: For X=6,C=(A+B)(10→X),X−1X=6, C = (A + B)^{(10 \to X)}, X – 1X=6,C=(A+B)(10→X),X−1
Answer: 1101

Now that you’ve seen the different approaches, what do you think? Did your solution match one of these answers, or did you come up with an entirely new method? We’d love to hear how you approached the problem, so feel free to share your thoughts in the comments section on Facebook!

This kind of puzzle is a fantastic way to keep your mind sharp and explore new ways of thinking. Even if math isn’t your favorite subject, challenges like this can be a fun and rewarding way to exercise your brain. So, whether you nailed the answer or found yourself scratching your head, we hope you enjoyed diving into this week’s math challenge!