Math problem brainteasers tend to be much trickier than the puzzles where you have to spot the difference. You must remember arithmetic from your childhood, pay close attention to detail, and think creatively.
The math equation below will require lots of creative thinking. It has two correct answers. Most people can figure out the more obvious answer but the makers of the puzzle (Go Tumble) say only 1 in 1,000 people can find the second answer.
If one of your answers was 40 then you're absolutely correct! If you add the sum of the first equation to the addends in the second equation, your answer is the sum of the second equation. Here's what this pattern looks like:
First equation: 1 + 4 = 5.
Second equation: 2 + 5 (plus the previous sum of 5) = 12.
Third equation: 3 + 9 (plus the previous sum of 12) = 21.
Fourth equation: 8 + 11 (plus the previous sum of 21) = 40.
Once you identify the pattern, finding an answer of 40 isn't too difficult. But can you identify another pattern among these equations and find the second answer? It's pretty tricky so you'll have to think outside the box.