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Matt71

Using the digit 7 five time, place the basic arithmetic signs in between the digits to obtain a total of 540

  • 2 years ago
  • 2 years ago

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  1. pratu043
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    nice question.....

    • 2 years ago
  2. Matt71
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    I know, it's been driving me nuts

    • 2 years ago
  3. pratu043
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    can you join two 7s together to form 77?

    • 2 years ago
  4. Matt71
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    Nah, you gotta put the signs in between each one

    • 2 years ago
  5. Matt71
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    You're going crazy, aren't you?

    • 2 years ago
  6. Stom
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    this question is right r u sure?

    • 2 years ago
  7. Stom
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    because if it is not then bad things will happen

    • 2 years ago
  8. Matt71
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    Yeth, I'm pretty sure it's the question

    • 2 years ago
  9. Matt71
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    And now everyone's thinking...

    • 2 years ago
  10. nikhil389
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    It would be fast to do with computer code, any one good with programming ?

    • 2 years ago
  11. wasiqss
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    certainly question of the week

    • 2 years ago
  12. Stom
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    yes certainly

    • 2 years ago
  13. TuringTest
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    if it doesn't get solved here put it in the meta-math section for future reference

    • 2 years ago
  14. Matt71
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    I've really been trying this for a while and I think it's messed up anyone else think it's impossible?

    • 2 years ago
  15. Matt71
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    as in, it's total overload here

    • 2 years ago
  16. jimmyrep
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    i'm not sure if this fits the rules but 77 x 7 + (7 / 7) gives 540

    • 2 years ago
  17. TuringTest
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    + - / and * only, right? no squaring or anything?

    • 2 years ago
  18. Ishaan94
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    concatenation isn't arithmetic right? nice work jimmyrep btw

    • 2 years ago
  19. Matt71
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    jimmyrep, if no one can find a solution without the placing two 7s together, I'll use your solution

    • 2 years ago
  20. jimmyrep
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    ok

    • 2 years ago
  21. pratu043
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    i don't think you can do it without joining two 7s together, jimmy rep has the right answer.

    • 2 years ago
  22. jimmyrep
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    77 is probably not allowed

    • 2 years ago
  23. wasiqss
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    jimmy rep yehh 77 not allowd

    • 2 years ago
  24. Matt71
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    It's probably not, but if it isn't I think it's impossible. I've been over this for over two hours, can't do anything to solve it. Yes, two hours, that's how obsessed I am with this question.

    • 2 years ago
  25. jimmyrep
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    these types of question are obsessive!

    • 2 years ago
  26. Matt71
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    Yep

    • 2 years ago
  27. pratu043
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    you can't do it because 540 is not divisible by 7.

    • 2 years ago
  28. Matt71
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    I KNEW IT! All that time wasted, I COULD'VE BEEN PLAYING TETRIS!

    • 2 years ago
  29. jimmyrep
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    lol

    • 2 years ago
  30. Matt71
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    Sweet baby turtles, I can't believe I missed that fact

    • 2 years ago
  31. TuringTest
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    that doesn't make a difference, you can make four 5's into 26 even though 26 is not divisible by 5 5*5+(5/5)

    • 2 years ago
  32. pratu043
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    Oh I see.....

    • 2 years ago
  33. moyo
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    in jimmy's example, he used 7/7 to add 1...

    • 2 years ago
  34. Matt71
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    Oh, yeah, then my time HASN't been a complete waste

    • 2 years ago
  35. Matt71
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    Good observation...

    • 2 years ago
  36. moyo
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    are parentheses allowed?

    • 2 years ago
  37. TuringTest
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    I would think so... it's just multiplication

    • 2 years ago
  38. Matt71
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    Yeah

    • 2 years ago
  39. moyo
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    i was thinking maybe there was an order of operations trick to solving it or something... grasping at straws :-)

    • 2 years ago
  40. shadowfiend
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    You don't need them though, order of operations takes care of the problem above.

    • 2 years ago
  41. jimmyrep
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    yes - i didn't need the parenthesis

    • 2 years ago
  42. sandra
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    It all depends on if digits can be stacked without operations (is 77 valid?) - in which case 7*77+7/7 works as jimmyrep mentioned

    • 2 years ago
  43. Matt71
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    question y u no make sense? ლ(ಠ益ಠლ)

    • 2 years ago
  44. shadowfiend
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    I feel like concatenation is needed here though. I'm not sure there's another way to grow the number fast enough while reserving 7/7 to make the difference of 1 you need to get to 540 itself.

    • 2 years ago
  45. wasiqss
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    this is certainly a crap question because 540 is not divisible by 7 and i advise ppl to stop wastin time on it

    • 2 years ago
  46. TuringTest
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    I already pointed out that the fact that 540 is not divisible by 7 makes no difference, read above

    • 2 years ago
  47. TuringTest
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    the problem is sitting in meta-math now, so it can be viewed in the future by someone who can figure this out, or prove it to be impossible.

    • 2 years ago
  48. Matt71
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    Sooooooo, you can't get a straight answer right?

    • 2 years ago
  49. TuringTest
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    not here, not now...

    • 2 years ago
  50. Tomas.A
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    this is correct answer

    • 2 years ago
  51. Matt71
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    Bummer huh

    • 2 years ago
  52. Matt71
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    Oh, well, guys I don't want to completely waste all your time

    • 2 years ago
  53. Matt71
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    So, if everyone please get together with the plan and just randomly give everyone you can medals!

    • 2 years ago
  54. TuringTest
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    Like I say, check the meta-math section in the future, someone will probably either find the answer or prove it impossible... eventually.

    • 2 years ago
  55. Matt71
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    Thanks, to everyone, for all the help

    • 2 years ago
  56. Stom
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    what an awesome way to waste time

    • 2 years ago
  57. TuringTest
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    :)

    • 2 years ago
  58. Matt71
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    Well, medals or wasted time right? Might as well

    • 2 years ago
  59. Stom
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    but to prove it impossible without a computers help is going to be interesting

    • 2 years ago
  60. TuringTest
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    moneybird has a knack for this kind of thing, but he's not around.

    • 2 years ago
  61. Matt71
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    Yep, but it's gonna take a looot of time and luck

    • 2 years ago
  62. Matt71
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    Yeah, something about koalas that makes him as smart as he is

    • 2 years ago
  63. TuringTest
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    jejeje...

    • 2 years ago
  64. Stom
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    yo

    • 2 years ago
  65. Stom
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    why r ppl still on this question, u u ppl stil solving it?

    • 2 years ago
  66. TuringTest
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    I'm thinking it is impossible: adding 7/7=1 is the only way I can see to get to a number that is not divisible by 7, which only leaves three 7's left over, and the most we can make that into is 7*7*7=343 taking 540-(7/7)=539 and 539/7=77 hence it seems jimmyrep's answer is the only one possible, but I don't think this is a true proof that it is impossible.

    • 2 years ago
  67. Janie29
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    I tried a bunch of different ways, and I can't find an answer. Now I have a Chem Final in 45min., and this problem is all I'll be thinking of!

    • 2 years ago
  68. Tomas.A
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    JIMMY IS CORRECT :P

    • 2 years ago
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