Very Few Can Crack This Puzzle In Under 20 Seconds…

Can You Find The Missing Number?

Today, we’re going to take a look at this problem that I found on the Simply Logical Youtube Channel…

I showed the puzzle to some of my peers, and out of the seventeen people I showed it to, only two people could correctly solve it in under 20 seconds. Here it is…

Image edited by author. (ORIGINAL IMAGE SOURCE)

To solve the problem, we need to find the missing number in the 3x3 grid shown above through pattern recognition.

You don’t really need a sheet of paper or a pen for this problem, so I recommend you try to solve it mentally!

If you want an additional challenge, time yourself such that you only have 20 seconds to figure out the pattern and apply it to find the missing number :)

Solution

Do you have your answer yet? Well, here’s the correct solution…

In every row in the 3x3 grid, the central number is the difference between the squares of the left and right numbers.

The central number in every row is the difference between the squares of the numbers on the left and on the right of the central row. (IMAGE SOURCE)

For instance, let’s take a look at 21 in the first row.

5², which is on the left-hand side of the middle number, is equal to 25. 2², which is on the right-hand side of the middle number, is equal to 4.

25 – 4 = 21. The pattern checks out for the first row.

Now, let’s try do the same for the second row. 4² = 16. 6² = 36.

36 – 16 = 20 . The pattern works for the second row as well.

Now, let’s find the missing number in the third row. To do so, we first need to find the value of 8², which is 64. Since 64 is greater than 55, we can just subtract 55 from 64 to get 9.

√9 = 3.

Therefore, the missing number is 3.

Could you solve this problem in under 20 seconds? Let me know in the comments section :)