Please do NOT post your answer, but do say if you think you have solved the puzzle and how long it took. Solution on Monday.

A puzzle via Tod B this week.  Can you figure out the secret of this sequence and so discover what numbers should replace the question marks?

111 = 13

112 = 24

113 = 35

114= 46

115= 57

117= ??

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.

101 comments

1. Laura says:

two minutes…

2. Seems very easy… worried I’m not seeing something tricky there.

1. Lazy T says:

yup, seems too simple if 116’s abscence is a mistake

3. Easy! Answer in maybe 8 seconds.

4. I have *an* answer in about 8 seconds, but I’d like to wait for Monday before claiming it’s right.

5. fifty2pickup says:

Dang, sorry just realied yr not meant to post the answer. I fail.

6. This one didn’t really need a spoiler .
I can’t really be that simple can it?

1. Dave's Neighbour says:

Agree, I’m not even going to bother

7. Jaq says:

Got it before I’d finished reading the question. Rather an easy one.

8. Selim says:

Yep, 2 seconds 😉

9. david dredge says:

Dumbing down again?

10. Anonymous says:

Took about five seconds.

11. kroketje says:

easy one!! a few seconds.

12. Rose-Marie Holt says:

Solved while reading it

1. Dave says:

Not a problem, just keep adding 11

2. Harris says:

101

3. Fotoflex says:

Depends on whether the post before it is 117 or 118.
At least, in my answer that’s important.

13. Anonymous says:

Very easy. Got it almost immediately

14. youngnedyoung says:

A few seconds! initiating smug mode (just for today. Or at least until 9am…)

15. Paul Durrant says:

I can see an answer, but it’s unsatisfying. I must be missing something.

16. MB says:

Hmmmm,
Why is there no 116=xx ?
And if my answer is correct then this is not a sequence that can be continued …….very unsatisfactory.

1. Anonymous says:

I could post the 116 = xx answer, but it might be deemed spoilerish.

2. Not really if you do it by multiplication then addition instead of just digit manipulation. Same answer as adding xx.

17. DiscoveredJoys says:

Seconds – but if it’s not the ‘right’ answer then it’s a better one!

Big headed? Moi?

18. Puzzle is void as 111 patently does not equal 13, etc.

19. Niva says:

Guessed the pattern after the first two, then verified with the other three. About 12 secs.

20. pete says:

Spotted the obvious pattern, but will wait till Monday – could be a red herring.

1. jcm says:

I spotted the pattern, too.

21. jcm says:

In less than 10 seconds.

22. Anonymous says:

I’ve spent 30 minutes on this and haven’t got a clue.

23. Anonymous says:

Worked out a rule for first example, checked it against others. Solved final case. Total time, 30 seconds.

If I’m right, it’s a really easy puzzle. If I’m wrong, it’s a really vague bad puzzle!

24. John Camble says:

79

1. Anonymous says:

Twat

2. I Love Twats says:

I love twats (unless they are self righteous, of course).

25. Anonymous says:

4 seconds

26. The Masked Twit says:

It is not clear to me why 116 is missing from the sequence.
The puzzle is either very hard (my time is then – not done yet and not counting) or trivial (my time then is 5 seconds).
In that a post consistent with the trivial version of the question has been pulled from the site I have to assume that it is a very trivial question.

TMT has now left the building.

1. Jeffrey says:

To trick you into coming up with the wrong answer by not really paying full attention.

27. Anonymous says:

not even a microsecond

you should try to keep the level of the site a bit better

better post at irregular intervals and when having nothing interesting not posting at all than posting useless things at regular intervals

1. Dave says:

Let’s see your blog then. Presumably it’s much better…

28. Stewart says:

About 30 seconds

29. Duncan says:

Hmm, I’ve got an answer but I reckon it’s not going to be the only one…

30. James Bailey says:

I think I’ve seen this one before – at least something very similar, so it only took a couple of seconds.

31. issa hamati says:

about 5 seconds.

32. Evan Cohrs says:

The answer would be 79. This took me three minutes to solve.

– Evan Cohrs

33. John says:

I have the same answer as most people, it feels like a Rat Trap.

34. Jim says:

Uhhhhh… Yeah, w a y too simple.

35. jpmoon says:

Less than 10 seconds

36. I’m kind of annoyed I didn’t say the answer in my first post this morning… Seeing as others post the answer afterwards but I can’t mw “prove” I was right…

37. Kristian says:

Linear regression!

38. ranger says:

Unless I’m missing something, about 10 seconds.

39. Miss Chili says:

15 seconds or less, depending on whether or not you want me to count my inner voice saying that I can’t do these maths puzzles…

40. Miss Chili says:

As for all the people who post answers when asked not to do, this is why I don’t read past the break until I’ve solved it or given up. /shrug

41. Heidi says:

easy one! About 2 seconds which is ruddy good for me 🙂

42. Cognitive Miser says:

There’s an easy solution and a slightly more difficult solution that I think the puzzle designer was shooting for.

1. Cognitive Miser says:

For those who solved it in seconds, what would your answer be for “231 = ??” ?

2. 16

3. Cognitive Miser says:

I see what you did there but I don’t think that’s the solution the puzzle designer wants (it’s hard to know because the first to digits in the examples are all 1s).

43. Anonymous says:

It took like 5 seconds.. We need more challenge!

44. Zbird says:

I’m sort of confident got it, but can’t be that easy, I’ll wait until Monday then probably have to groan!

45. After 10 seconds I had one answer. After 30 I had two answers, both of which seem to work.

46. Anonymous says:

Hm, I see at least two solutions and both seem equally good.
1. Linear progression. If this is the answer, then why choose 111 as the first element – beyond me. In this case each pair will be unique.
2. A little bit more convoluted, involves some arithmetic and rearrangement. In this case 111 will no be different from 21.

1. John says:

That isn’t it .

47. after 10 secs, i have an answer, but with the feeling that it is not what is intended.

48. I think I came across this in second grade arithmetic. Is there something I’m missing? Quite possibly the lowest challenge to date..

49. The “obvious” answer seems so trivial that it hardly seems worthy of calling this a puzzle. If there’s a more interesting answer, it’s too bad a case that doesn’t fit the obvious one wasn’t given.

50. John says:

I believe I solved it and it took me 1 and a half minutes. 1 minute is for when I was reading the puzzle.

51. John says:

For those who need a hint, think of first grade addition when you solve this. For those who know the answer, what would this be: 1000: ??

1. 1

52. John says:

10, 100, 1000 are all the same.

53. Mark says:

I get three answers. First obvious one starts with 7 which most people will have. Other answers both start with a 6

1. If you apply the principle of Occam’s Razor, the obvious one is the right one. I suspect an infinity of possible answers exist, but in this case they will all be more complicated than the immediately obvious one.

2. Jeffrey says:

I’m sure an infinity of answers are possible. Most of them will be wrong.

54. Chase says:

The way it is presented there are two ways to go about answering it that both come to the same conclusion for 117. What would the answer for 1234 be? If you approach it from a computer generated logical point of view (which I assume you aren’t) then the answer is 12366. If you approach it from from the a symbolic point of view then it shares an answer with one of the examples you were showing already (I preferably don’t want to say since I’m guessing this is the solution that was intended).

1. Chase says:

Correction on that post: It doesn’t share an answer but gives a very obvious hint.

55. Jeffrey says:

Please tell me this isn’t the Friday puzzle.

56. Matt Atkins says:

79, about 30 seconds.

Sent from my iPad

57. cuda says:

Almost too easy, unless I’m missing something here

58. Mya says:

It took me 20 seconds. This is this easiest one I’ve seen, but a good one. Keep these awesome mind bending puzzles coming!

59. I got an answer within a few seconds which is consistent with the list, but it doesn’t seem very satisfying. There are probably much more sophisticated answers which are more difficult of convoluted.

60. Roberto says:

I identified 2 patterns both work. One you had to be clever when 116 is missing the other one it doesn’t matters. Anyone else?

61. Fotoflex says:

I have a different answer, the number is smaller than you think. 🙂

62. Fotoflex says:

If the next number were to be 118, that would make 80. 🙂
Anyone else got that?

63. Fotoflex says:

Unless it’s 119, that would make 81.

64. Merari says:

15 seconds

65. mightyhero says:

Too easy.

66. sidney18511 says:

79

67. chritter says:

I have 2 answers therefor im confused on which one to use I can explain if needed

68. chritter says:

I got 79 and 117
111=13
112=24
113=35
114=46
115=57
116 was missing it would be 68
117=79
your adding by 11

69. chritter says:

but if you do
111= 1+1+1=3*13=39
112= 1+1+2=4*13=52
113= 1+1+3=5*13=65
114= 1+1+4=6*13=78
115= 1+1+5=7*13=91
116= 1+1+6=8*13=104
117= 1+1+7=9*13=117
there for it would be 117=117
so which one is right
79 or 117

70. I found four answers (excluding the 1111) three of which had the same answer. THEN I saw the sequence used as an example! So altogether it took 10 mins or so.