If you love a good brainteaser, this tricky little equation might just be your next favourite challenge. At first glance the brainteaser shared on the smashing pencils TikTok, seems like a simple sum, but there’s a clever twist behind the numbers. Ready to put your thinking cap on and figure it out? Let’s see if you can crack it.
Here’s the equation that’s been leaving people scratching their heads. 1 + 1 = 5 2 + 2 = 20 3 + 3 = 45 4 + 4 = ?. At first glance, it looks like basic addition, but something is clearly off. The numbers don’t add up as you’d expect. If you are stumped then don’t worry you aren’t the only one. There’s a pattern at play here, and once you spot it, the solution becomes clear.
The trick lies in using the first number of each equation as part of a sequence. Instead of just adding, you multiply and then add the result multiple times, depending on the first number. It’s all about recognising the underlying sequence. Look away now if you want to figure things out yourself.
To solve it, you need to understand that the first number of the sum is multiplied by 5, and then the result is added to itself as many times as the first number. Here’s how it works:. For 1 + 1, you start with the number 1. Multiply it by 5 (1 x 5 = 5), and that’s the answer. For 2 + 2, you multiply 2 by 5 (2 x 5 = 10), and then you add 10 to itself (10 + 10 = 20). For 3 + 3, multiply 3 by 5 (3 x 5 = 15), and then add 15 three times (15 + 15 + 15 = 45). Finally, for 4 + 4, multiply 4 by 5 (4 x 5 = 20), and then add 20 four times (20 + 20 + 20 + 20 = 80). So, the answer to the puzzle is 80!.
