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Some interesting brainteasers Starter I used

  1. Dec 23, 2009 #1
    Some interesting brainteasersStarterI used

    Some interesting brainteasers

    Starter



    I used factorials for this one, but it will be interesting to see how you attempt your answer.

    Head Scratcher



    These questions are designed so that any body above the age of about 13 can answer them without much mathematical experience.

    If this is a success then I will reveal the answer this time next week and come up with a new one [MONDAY 28TH DECEMBER 2009]
     
  2. jcsd
  3. Dec 23, 2009 #2
    Re: Brainteasers!

    Brainteasers factorial?
     
  4. Dec 23, 2009 #3
    Re: Brainteasers!

    I thought he might mean: 1!

    DaveE
     
  5. Dec 24, 2009 #4
    Re: Brainteasers!

    Am i missing something? whats the brainteaser?
     
  6. Dec 24, 2009 #5
    Re: Brainteasers!

    That's the brainteaser.
     
  7. Dec 24, 2009 #6
    Re: Brainteasers!

    Oh, I assumed that there was some math problem that i was missing.
     
  8. Dec 24, 2009 #7

    D H

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    Staff Emeritus
    Science Advisor

    Re: Brainteasers!

    There is something missing. The problem is, what is the problem???
     
  9. Dec 24, 2009 #8
    Re: Brainteasers!

    Thats what i said.
     
  10. Dec 25, 2009 #9
    Last edited: Dec 25, 2009
  11. Dec 28, 2009 #10
    Re: Brainteasers!

    And for the ladies, it's in the same place.
    48
    8
     
  12. Dec 28, 2009 #11

    Borek

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    Staff: Mentor

    Re: Brainteasers!

    You've missed the idea - it is not about finding questions, but about finding answers.
     
  13. Dec 28, 2009 #12
    Re: Brainteasers!

    How did you do this?

    Considering how I wasn't sure about how to do the questions
     
  14. Dec 28, 2009 #13
    Re: Brainteasers!

    For the first one, I counted. I did use a factorial, but it wasn't a big part of the solution.
    For the second one, I graphed a few points and the figure appeared.
     
  15. Dec 28, 2009 #14
    Re: Brainteasers!

    What was your factorial (my teacher for pre-calculus didnt teach)?

    For the second, doesnt the function go to infinity?
     
  16. Dec 28, 2009 #15
    Re: Brainteasers!

    The second one is pretty much 4 triangles in the four quadrants with vertices
    (-2,0),( 0,2) ,(0,0)

    (2,0),( 0,2) ,(0,0)

    (0,-2),( 0,0) ,(2,0)

    (0,2),( 0,0) ,(2,0)

    The area is simply ( 0.5(2)(2)) *4 = 2*4 =8
     
  17. Dec 28, 2009 #16

    Borek

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    Staff: Mentor

    Re: Brainteasers!

    Wow, I have even no idea what it does mean and Jimmy was able to solve.

    Edit: what do we know about colors assigned to dices? What color is four sided dice? Six sided one? Ten sided? Twelve sided? Twenty sided? Not sure what types I had, I can't find my set form RPG times.
     
    Last edited: Dec 28, 2009
  18. Dec 28, 2009 #17
    Re: Brainteasers!

    It is? http://www.wolframalpha.com/input/?i=|y-x|+|y|+=+2
     
  19. Dec 28, 2009 #18
    Re: Brainteasers!

    For instance, you could roll a red - 1, orange - 2, yellow - 3, and purple - 6. The product is 36. That's 1, now go find the other 47.
     
  20. Dec 28, 2009 #19

    Borek

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    Staff: Mentor

    Re: Brainteasers!

    Plush_20_Sided_Dice.jpg

    red - 12, orange - 1, yellow - 3, purple - 1. Now I need only 46.
     
  21. Dec 28, 2009 #20
    Re: Brainteasers!

    I attempted it by finding combinations of 4 whose product is 36 (assuming that they were all 6 sided dice).

    I think i got:

    1,1,6,6
    1,2,3,6
    1,3,3,4
    2,2,3,3
    1,3,3,4

    I might have missed one combination. But, since there are 4 identical dice, each one could fill one of the spots. So wouldnt it be 4!*5? Which is 120
     
    Last edited: Dec 28, 2009
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