# Most People Can’t Spot the Missing Number in These Sequences in Under 10 Seconds–Can You?

February 3, 2020 Updated: February 3, 2020
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Can you identify which number is missing from the following sequence in under 10 seconds? Rumor has it that most people can’t beat the clock; why not see if you are part of the puzzle-solving elite and give it a try?

All you need to do is put 10 seconds on the timer, and when you’re ready, push start and start scanning the sequence of numbers in the pink box below, and identify which digits are missing. It’s not, however, quite as easy as many people think.

If the missing number doesn’t easily reveal itself, simply scroll down to see the solution below. For anybody that succeeds, however, we have two further challenges lined up, each a little harder than the last.

The number missing from the sequence of 1 to 13 in the pink box is, of course, the number 4! Did you notice?

If you did, you can count yourself among the minority in having exceptionally keen observation skills; rumor has it that the vast majority of challengers fail to beat the clock.

This second puzzle is just like the first only with more numbers. Set a timer for 10 seconds and try to identify the missing number.

As for the solution to the second puzzle in the red box, the missing number is 18! Did you find it?

If you did, you are two-thirds of the way toward being able to congratulate yourself for beating thousands of netizens to the correct solution.

Now, a real challenge!

The third and final puzzle is the same idea as before but with far more numbers this time. A sequence of numbers between 1 and 60 fills the blue box below, but not every number in the sequence is represented.

Experienced puzzle fans may gloss quickly over the sequence and identify the missing number in no time, but for others it may be harder. Consider putting 20 seconds on the clock for this final challenge.

Set your timers and … go!

Before the solution is revealed, note what hundreds of puzzle lovers have already commented on their own joy at taking part in the challenge.

When this last puzzle was shared on Facebook, many commented that they had found the solution in a matter of seconds. Others simply shared how much they loved taking part.

“Not too difficult,” one person wrote. “Years looking at lists of stock numbers trains the eye I guess!”

As for the solution, the missing number in the third and final number sequence is, of course, 39! Did you notice this omission in under 20 seconds?

These brainteasers can increase mental focus, cognitive aptitude, and even your attention span. Millions of netizens use them as a mental pick-me-up in the middle of a long working day, and the benefits can be innumerable.

There’s a solid scientific reason as to why it can be so hard to identify the missing element in a sequence. Our brains are trained to recognize sequences, and for efficiency, we often fill in the gaps between the beginning and end of a familiar sequence of any kind, whether or not all of the constituent parts are really there.

The issue of sequencing has interested cognitive neuroscientists for years. Dr. Graham Rawlinson of Cambridge University even wrote his PhD thesis on the phenomenon that “randomizing letters in the middle of words [has] little or no effect on the ability of skilled readers to understand the text,” as quoted by the Independent. The now-viral, mind-boggling example reads:

# The huamn mnid deos not raed ervey lteter by istlef, but the word as a wlohe.

If you enjoyed these challenges, share them with a friend or family member!

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