Do you hate being kept in the dark? An unsolved mystery can haunt you, rattling around in your brain like a ghost.

We may never get answers to some of history’s biggest mysteries, such as the truth about the Bermuda triangle, the location of Cleopatra’s tomb or the identity of Jack the Ripper.

But we have an enigma you can solve in minutes, and it may even help to keep your brain sharp. Brain teasers like this one may boost your language ability, memory and problem solving skills.

If you’d like to play detective, this mystery number brain teaser will require you to use both logic and math skills. Using only the numbers on the page as clues, you’ll have to decipher the identity of the final missing number.

Math games like this one may help keep your brain strong and flexible through development of new neural connections. Number games also may make you quicker at everyday calculations, from figuring out how many bags of Halloween candy to buy to making sure you get the right amount of change back at the store.

**Check out the bottom of the page for the correct answer.**

**Answer**: 17 | The middle number equals the top number times the bottom number plus the left number times the right number.

** Did you solve the mystery number puzzle? If so, comment to clue us in on how you did, how long it took and your favorite unsolved mystery**!

Very straightforward.

I like challenges like this one!

This one I solved more quickly – about a minute.

got it in about 4 minutes

Less one minute

That took me less than a minute. When I saw that the first centered number was prime, I knew that ruled out certain possibilities for what was wanted. The second set of numbers is what then became obvious to me and then it was easy. This kind of math problem is okay, but I’ve always hated the ones that went… If Johnny went to Kansas in a boat and Miriam stayed behind and knitted, then what time did they eat dinner? Huh? And by the way, who cares? 😂

It took ten minutes max and I figured out the answer. I was very proud of myself.

I didn’t know I should time myself, but I easily came up with 17. It was fun, thanks!

Another fun puzzle!

What was said above but times each then add answers to get middle number

It took me about 3 minutes to figure out that the third set middle number was 17. I multiplied the numbers across from each other then added the two totals together.

1 min to get the answer

That was fun! Probably because I figured it out in aboutv5 minutes.

Wow, tricky.

Does anyone know the formula or equation for figure 1 and figure 2

how middle number 43 and 30 was calculated

Look at comments they explain it well

Solved a couple of minutes.

It took me about 10 seconds by multiplying the numbers and then adding the numbers. No clue needed.

Sorry I forgot, it took about 2 minutes.

The middle number of the first set minus the middle number of second set is 13, so I subtracted 13 from the second set and that is 17 which is the middle number for the third set.

It was too easy. I stumbled on the answer in less than a minute.

It took me 1-2 minutes

Multiply to and bottom and side to side and and together. 17.

I like math puzzles. I solved this puzzle in less than a minute. I first added the numbers in the first puzzle and it wasn’t the right answer.. Then I multiplied the top and bottom and right and left and added them together. It worked for all 3 puzzles. Thank you! I enjoyed it.

17

I experimented with different ways to combine the numbers on the outside to get the center number. It took me about 2-3 minutes to come up with the answer.

I eliminated other options. It took me a couple of minutes. I tried adding all the outer numbers and that didn’t equal the center number. Then I figured it out.

found the answer in 3 minutes no clue needed

It took me about a minute. I like basic and intermediate Sudoku puzzles. I don’t understand how to work the higher level Sudoku. The ones I am successful with are fun when they take on their own life when about half solved.

took about 30 seconds to solve

just trial and error, by multiplying the outside numbers before adding them together, took less than a minute

It took me like 10 minutes.

Knew it had to be a combination of multiplication and addition.

13 from 43 was 30, then 13 from 30 was 17. Answer 17.

I just subtracted the middle number in the second figure from the middle number in the first figure. I used that number and subtracted it from the number in the middle number of the second figure to get the number in the middle of the third figure. I got the same answer (43-30 = 13; 30-13. = 17)

I solved it within 3 minutes. It was obvious that it was not about adding the numbers, so I next tried multiplying them. The first answer, 43, is odd, so a quick evaluation of the numbers around it made it obvious that the result would be an odd number.

I did solve the puzzle. About 2

Minutes.

17

30 seconds I solved it.

Multiply top number with bottom number and multiply side numbers then add the totals together

Yes, it was pretty easy. I like working with numbers but not letters.

Solved in less than 1 minute. My favorite unsolved mystery is how was stonehenge built?

I attained the correct number, 17, in ten seconds. Of course, I’m a retired math teacher.

Yes, I solved the puzzle

Solved it