Answer to the Friday Puzzle….


On Friday I posted this puzzle…..

What value should ‘x’ be in the following sequence?

16    06    68    88    x     98

If you have not tried to solve the puzzle, have a go now.  For everyone else, the answer is after the break!

If you turn the sequence upside down you get….

86   x  88   89   90   91

so the missing value is 87!

Did you solve it?  Any other solutions?

I have produced an ebook containing 101 of the previous Friday Puzzles! It is called PUZZLED and is available for the Kindle (UK here and USA here) and on the iBookstore (UK here in the USA here). You can try 101 of the puzzles for free here.


93 comments on “Answer to the Friday Puzzle….

  1. AMWhy says:

    Seeing as your answer is upside down, you haven’t quite answered the question correctly. The real answer should be L8.

  2. Roland says:

    I would say that the answer is L8 !

  3. Anders says:

    Shouldn’t that be L8 (87 upside down)?

    …and since I believe in honesty I admit that no, this one I didn’t get

  4. Narfix says:

    I agree with the previous comments.
    The answer should be 87 upside down which doesn’t have a real value therefore it is not the proper answer.

    • Goliath says:

      That’s why I didn’t think the answer was satisfying. Ah well, sometimes it’s not only out of the box thinking but also out of the box looking.

    • Daryl says:

      I stand by the fact that a string is a value

  5. Noel says:

    I am beside myself now .
    How obvious does the answer and all the clues need to be.
    This was at me all week end.

    Well played Mr Wiseman.

  6. Rob J says:

    My answer was also “L8”, although I think a better answer would be “87 written upside down”

  7. Alan says:

    Tried turning my iPhone upside down to see this… Doesn’t work, does it? The screen flips!

    • Michael says:

      Hold it face up, then turn it as you would a compass.

    • says:

      Freeze your Iphone first. Double click and slide the bottom menu to the right. Then Lock the button on the lift and the screen will not flip

    • Joe says:

      There is a rotational lock on iphone4 to 6. Drag the tab upward from the bottom and it is the rotation icon with a lock in the center of it. You really should read your manual or explore your phone a little.

  8. Jerry says:

    I got 87 as well, but only after reading some of the clues about “point of view” etc. That were posted on Friday. I also agree that a better answer would have been “87 written upside down.”

  9. @franmartinez_ says:

    crazy! i didn’t try this way for obvious xD

  10. Simon says:

    I am proud to say I got this one but only because I’m lazy and on Friday was reading it in bed so was already reading it sideways. 🙂

  11. Stephen says:

    I agree that this puzzle doesn’t work because 7 doesn’t have an upside down variant.

    As 2 works upside down (more so in some fonts than others), I think a working sequence could be: 26 16 06 68 88

  12. Ben says:

    Richard should have written l6 in the question instead of 16, otherwise it is a good one. I didn’t get it.

  13. Edgar says:

    I think I got it right, but I didn’t know hiw to type a 7 upside down 😦

  14. David Mathew says:

    Good one, Richard. I wasn’t even close.

  15. Chris Emerson says:

    It should have be L8, as everyone else has said!

  16. Stuart says:

    You asked for the missing value in this sequence: 16 06 68 88 x 98

    Not this one: 86 x 88 89 90 91

    Answer should be L8!! 87 is simply wrong!

  17. Kate says:

    I got 88.
    If you swivel each digit of 68 you get 98, which is on the other side of x
    So I swivelled 88 to get 88.

    • David says:

      I did the same thing. 🙂

    • Kelly says:

      I agree with you that that would work, but only if there were four digits to the riddle: 68 88 x 98. The 16 and 06 would basically serve no purpose, otherwise. Nice thinking though! 🙂

  18. Robert says:

    I thought the best answer was ’48’, but this depends on how you write your 4. Mine is basically identical to an upside-down 7, with a short line through the top of the 7.

  19. SereneBlueSky7 says:

    I’d say it’s 10, 20 and 30. You have to extract them from the next number. 🙂 That’s what I see in it.

  20. patrick says:

    yup – consensus – the puzzle is a cheat, answer is wrong.

  21. SereneBlueSky7 says:

    Okay, I was wrong. But that does fit for the first two. 16-6=10, 88-68=20. 🙂 98-x=30, which makes x=68

  22. Ben says:

    According to, the answer should be ㄥ8.

    Or should I say:
    87 ǝq plnoɥs ɹǝʍsuɐ ǝɥʇ ‘/ʇǝu˙ʇxǝʇdılɟ˙ʍʍʍ//:dʇʇɥ oʇ ƃuıpɹoɔɔɐ

    • SimonP says:

      ˙ʇsıqnɔ ʇıq ɐ sʇǝƃ puɐ pɐdǝʇou oʇuı ʇxǝʇ uʍop ǝpısdn ƃuıʇsɐd ʎɹʇ ¡¿ʞɹoʍ uǝʌǝ ʇı sǝop ʍoɥ ˙looɔ ʎllɐǝɹ sı ʇxǝʇdılɟ ˙ʍoʍ

      You can copy upside down text in and it puts it right way up again. Awesome!

  23. Henry says:

    I was sorely tempted to make a bunch of puns on Friday about lateness, the White Rabbit and so on, but that would have been pushing the limits. Anyone who used to do calculator puzzles would get this right away.

  24. NoAstronomer says:

    I did get this on Friday after about 5 minutes of telling myself it wasn’t a simple math problem. However, as other commenters have pointed out, 87 is *not* the correct answer.

    • Michael says:

      Technically yes, but saying “87” is a sure indication that one took the mental leap to solve the puzzle. Enough to pass a recruitment exam, say.

  25. thekendon says:

    87 can be the correct answer without being upside down. The puzzle is to find x; the x in the sequence could be upside down just like the numbers. If this were the case, 87 would be the correct answer.

  26. Jon d says:

    I got stuck thinking it was the number of loops used in writing each number, that sequence starts 1,2,3,4.. Never got as far as turning it upside down.

  27. bletherskite says:

    I’m happy. I got this one quite quickly after reading some of the comments and having an epiphany. Confess if I hadn’t read the comments I would probably have been scratching my head.

  28. Marion says:

    I guessed that the numbers could be turned upside down but didn’t think that through far enough to get the correct answer, never mind there’s always next week!

  29. Sorry, a bit late on this one. Another solution to this puzzle you might find amusing is the following:

    With x=24344

    the given sequence (16 06 68 88 x 98) is the same sequence of numbers in pi starting at the 48,796,848th digit (counting from the first digit after the decimal point).

    e.g. See:
    and search for 16066888 then find the next 98 by eye. The numbers between give x.

    As you might imagine, this is not a coincidence nor magic, but rather almost statistical certitude since the digits of pi are (essentially) random for all practical purposes. The sequence 16066888 occurs roughly where you expect a random 8 digit number to occur in a large sequence. However, it is actually a lucky coincidence that that 98 occurs within a few digits of the last 88 so can be seen quickly by eye.

    Although perhaps cute, this is a kind of cheater solution because any arbitrary sequence can be found in this fashion in principle (not just limited to pi, but e, sqrt(2), and other large quasi-random sequences).

    • Raja Halazon says:

      yes ,indeed, your reply is most learned that I have seen..

      ,reading backwards or bottom to top or side ways is simply not a puzzle but a dizziness test?

  30. الإنجليزيةالعربيةالإسبانيةAlpha
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    Thanx Aaddiqi

  31. Anonymous says:

    I could not have tired: (
    Thanx Aaddiqi

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  33. HenryUK says:

    Gosh ! Why on earth people don’t get the essence of the question rather than questioning the beauty of 7 when it is written inverted ?….. To all those gus who think the answer is L8 – do you see any other number with 7’s in the lot… That is indeed the whole purpose. Test your mental ability rather than questioning the beauty of 7 when written inverted. Common sense is so uncommon now a days after the invention of iphone may be. I am really sorry to say this.

  34. 87………flip the text u will get this value……

  35. pravin prabhakar says:

    16 ,06 ,68,88 ,x ,98


    ans= 58

  36. Daryl says:

    I like the “87” answer as it has you thinking out of the box. I think the proper mathematical number is 58. The response though should have read:
    16, 06, 68, 88, x, 98
    16-06 = 10
    68-88 = -20
    x-98 = 40

    The problem with that answer is that the answer falls apart when you try to determine the next number or two numbers in the sequence. You only know that the 7th number minus the 8th number will equal -50.

  37. HenryUK says:

    Hi Daryl
    I agree, this question could be asked in a different way to stimulate lateral thinking
    For e.g, check the image I have created for a question and uploaded in the link below

  38. quote a couple of your articles as long as I provide credit and sources back t

  39. You got me there! Good one.

  40. Anonymous says:

    step 1 (68-16=52)
    step 2 (88-6=82)
    step 3 (98-88=10)
    step 4 (82-52=30)
    step 5 (30+10=40)
    Ans is (68+40= 108)

  41. Anonymous says:

    16+6 = 22
    68+88 = 156
    156+98 = 254

  42. Anonymous says:

    I thought it would be 88 based on the number of circles in the numbers. 1-2-3-4-X-3

  43. Anonymous says:

    Hi all.

    The puzzle should be given in the form of an image. It shows a car parked in a space where the ‘x’ is. The numbers correspond to the other parking spaces. You’re given the view so that the back of the space (the side furthest from the road) is towards you.

    Based on this view, you can turn the numbers upside down as it were – the perspective for ‘seeing’ the number should be viewed from the perspective of the driver. So he sees 86-87-88-89-90-91.

    Why he chose 87 remains a mystery. Perhaps he likes numbers divisible by both 3 and 29? Or is now aged 27? Or 28, if you’re picky.

  44. Anonymous says:

    the answer is 128 the difference between the first two number is 10 16 and 6 and starts with d larger number 16. the diff between the 2nd sets of numbers is 20 68 and 88 and it starts with the small to the bigger number and since its a sequence and follows a pattern, d last sets of numbers must be 30 diff apart which make d likely candidates 68 n 128 and since a number can not repeat in a sequence d answer is 128

  45. Karen says:

    Hello! I found 78… because after you find 87, don’t you have to look upside down again? What do you think?

    • I think it is 78, also. I disagree with all the 87 answers. Looking at the numbers right – side up, knowing they are relfected, u could see the answer is 78…… I understand how people get 87, but don’t think it is the right choice.

  46. Anonymous says:

    The correct answer is 58.

  47. 6 16 68 78 x 98 ? what is this puzzle answer and how it .??

  48. Roy says:



    a pattern of -10 +20 -30 +40 -50 etc…

  49. KK says:

    With this illustration we agreed with 87 is a correct answer

  50. Raoul says:

    My answer is 128, which is the only logical answer. Your 128 is not that obvious.

  51. Raoul says:

    Apologies, I meant to say you 87 is not that obvious. You take 16 and 06, which give a difference of ten in the order big, small. Then follow 68, 88 where the difference is 20, in the order small, big. So logically the next difference is 30 in the order big, small again. Add 30 to 98 to get 128. Therefore I reject your answer of 87 on the basis that you cheated! :-))

  52. PRATIK says:

    87 ANSWER IS WRONG !!!!!!

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  54. anil kumar vishwakarma says:

    I think there is another way to solve that is little bit a type of mathematical puzzle.
    16 06 68 88 × 98
    If we go in this manner -10 +20 -30 +40 -50 +60 ………………
    ( × – 30)=98
    So value of × would be 128

  55. You’re wrong. 87 is the correct answer. Though this view shows the other spots as numbers upside down we can all agree because of the sequence the answer is 87. It doesn’t say what would the number of this parking slot look like from this view. It says what is the number of the parking slot? Yes from this view the 87 would look like L8 in this picture. But that doesn’t change the number of the actual slot.

  56. Jonan says:

    The number of the sequence is 17, if the second is 3 what is the first number.

  57. Anonymous says:


  58. Anonymous says:

    Consider alternate sequence:
    06, 88, 98
    Here 88-06 = 82
    98-88 = 10 (= 8+2)

    On similar logic
    16,68, ?

    Here 68-16 = 52

    So next number will be (5+2) + 68 == 75

  59. deepak says:

    I think 93 is the ans…..
    Que is 16 06 68 88 _ 98 ?
    Ans: 61 60 86 88 _ 89
    So ..61 – 60 = +1
    86 – 88= -2
    X – 98=+3

  60. deepak says:

    Ans is 93…

  61. deepak says:

    Sry its X – 89= +3

  62. deepak says:

    Once agin sry…93(39)..
    Ans is 39.

  63. JamaicaJoe says:

    It is 58. I can’t believe how many people got this wrong.

    • Tom Groshens says:

      It not a matter of any formula. The answer is from looking at the numbers upside-down. 87

  64. Anonymous says:

    Can you please break down this question I’m only in 6th grade.

  65. mcjarod says:

    Yo en un principio me imaginaba que se restaba 10 luego se sumaba 20 al que luego se restaría 30 así que pensé en el 128

  66. Anonymous says:

    Its 87 because if you look, at it upside down you see thatit adds up one

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