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Riddle 1961

  1. May 28, 2004 #1
    1. What happened in 1961 that will not happen again for over 4000 + years?

    2. A man wanted to enter an exclusive club but did not know the password that was required. He waited by the door and listened. A club member knocked on the door and the doorman said, "twelve." The member replied, "six " and was let in. A second member came to the door and the doorman said, "six." The member replied, "three" and was let in. The man thought he had heard enough and walked up to the door. The doorman said ,"ten" and the man replied, "five." But he was not let in.
    What should have he said?

    3. PERFECT WORD is a word in which ANY one letter could be replaced by another letter to form another word. An example of a 4-letter Perfect Word is CAST because C could be replaced by L to form LAST or A by O to form COST, or S by R to form CART, and T by E to form CASE.

    Give a 6-letter Perfect Word.

    4.Can you find the largest number possible containing any of 9 of 10 digits, considering 0 also a number, that is divisible by 11 without a reminder?

    Good LUCK! :smile:
     
  2. jcsd
  3. May 28, 2004 #2
    i can only solve this one, i don't know about the others...<<<<< SMILIES >>>>>

    Is it 3 and the last one will say 1.5 ? :tongue2:

    -Ali.and.the.40.thieves,
     
  4. May 28, 2004 #3
    Is that a guess or is there a logical reason for giving the solution??
     
  5. May 28, 2004 #4
    how can you say it is a guess ? I tried to think and computed as correctly as i could....
    12/2=6
    6/2=3
    3/2=1.5
    Thats a Logical reason ?????
     
  6. May 28, 2004 #5
    If dividing by 2 is your logical response. Then if the guard said 10, then you should have replied 5. But that is not the case, as written in the question. This question is not as simple as just simply dividing by two!!
     
  7. May 28, 2004 #6

    marcus

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    the word twelve has 6 letters
    the word six has 3 letters
    the word ten has 3 letters

    he said 5 and was not let in, so he should have tried saying 3 instead,
    maybe that would have worked

    I like these riddles, thank to K.I. for posting them
     
  8. May 28, 2004 #7
    oh well, :tongue2:
     
  9. May 28, 2004 #8
    marcus is correct! The answer to the doorman's numbers was the number of letters in the word he said. There are still 3 more unsolved questions, good luck!
     
  10. May 28, 2004 #9

    marcus

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    K.I. here is just a guess, I didn't check it to see if it is the largest
    but only that it is fairly large, and it uses each of the digits from one to nine exactly once, and it is divisible by 11


    978653412

    I didnt use a computer, someone who wants to write a short program in basic computer language could quickly find out what is the largest
     
  11. May 28, 2004 #10

    jcsd

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    1. Tottenham Hot Spurs won the double in 1961, they won't win it again 'til 6009 (i.e when the last two digits of the year are first 2 upside-down)
     
    Last edited: May 29, 2004
  12. May 28, 2004 #11

    jcsd

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    I reckon it's 987645230.

    I guessed this using the test for divisibilty for 11 i.e.

    9-8+7-6+4-5+2-3+0 = 0
     
  13. May 29, 2004 #12

    jcsd

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    Canter:

    banter
    center
    carter
    cancer
    cantor
    canted

    Thinking of a 6-letter perfect word was hard as (to me anyway) there are no obvious ones and there are words like 'hanger' in which all the letters but one can be replaced.
     
    Last edited: May 29, 2004
  14. May 29, 2004 #13

    jcsd

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    Actually I'm being silly, you can get eveb bigger numbers using the test

    e.g. 987652413

    as:

    9-8+7-6+5-2+4-1+3 = 11

    A quick test confirm that 987652413 is the highest such number.
     
    Last edited: May 29, 2004
  15. May 30, 2004 #14
    Wow, it seems like all the riddles are solved. Good Job all!!
     
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