Telha
I understand that some people are naturally inclined to enjoy math, while others (myself included) find it utterly unappealing. Personally, I like to think of myself as more of a creative thinker than a logical one. But hey, everyone’s different.
That being said, while I never enjoyed struggling with math in crowded, chaotic classrooms, I’ve recently discovered an unexpected enjoyment in solving online puzzles and riddles. I tackle them at my own pace, with no pressure or deadlines, and I find the process oddly satisfying. It seems I’m not alone in this newfound hobby — there are plenty of people out there who thrive on spotting patterns and cracking challenging math problems.
With that in mind, we decided to test our readers’ problem-solving skills with a brainteaser that has left many on the internet scratching their heads. Ready to put your thinking cap on? Here’s this week’s mathematical challenge:
If 1+4=5, 2+5=12, and 3+6=21, what is the value of 5+8?
To make it clearer:
1 + 4 = 5
2 + 5 = 12
3 + 6 = 21
5 + 8 = ?
This puzzle has sparked plenty of debate online, with people divided on the correct answer. As with most riddles, your approach determines the outcome. And here’s the twist: there’s more than one correct answer! In fact, there are several ways to solve this problem, as our research reveals.
If you’ve tried solving it or, like me, reached a point of frustration and simply need to see the solution, here are five different methods to tackle the 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’, where 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+2}, where C’ is the previous answer. A and B are not used in the equation.
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 -1}. First answer in Base 6, then Base 5, then 4, etc.
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 -1}, including “missing” numbers.
Answer: 1101
So, which method did you use? Or did you come up with a completely different solution? Let us know how you tackled the challenge!
