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Following logical quiz help

  1. May 21, 2007 #1
    I have below logical quiz but can not seem to find a reasonable answer.
    Any comment or help will be appriciated.

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    A blind man has a draw of socks with 2 dark blue socks, 3 yellow socks, 2 brown socks, and 4 white socks randomly scattered. He has an important function and wants to wear matching socks so decides he will select a number of socks and stop at a sighted friends house on the way that can help him select a matching pair for the function.

    1. What is the least number of socks he need to take to his friend’s house to ensure he has a matching pair?


    2, What is the least number of socks he needs to take to his friend’s house to ensure he has a ‘dark’ matching pair?


    3. Our blind friend is given two more socks, both the same dark blue colour, that he adds to the draw. The next day he is in the same predicament, an important function and he wants to have matching socks. How have the answers to questions one and two changed? Why?

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  2. jcsd
  3. May 21, 2007 #2
    1. If he chooses 5 socks, then is ought to have a pair since you cannot have 5 different colors of socks.

    2. If he chooses 4 + 3 = 7 socks, they could all be light. He thus needs to choose more. If he chooses 7 + 2 = 9, the the two extra could be of different color. So that gives us 7 + 3 = 10, since in 3 selections, two have to be of the same color.

    3. See above; everything said still applies, nothing changes.
     
    Last edited: May 21, 2007
  4. May 21, 2007 #3
    A question... what do you mean by say 3 yellow socks?

    is it 3 pairs of yellow socks or just 3 single socks?
     
  5. May 21, 2007 #4
    It says it clearly...
     
  6. May 21, 2007 #5
    So... which one? :confused:
     
  7. May 21, 2007 #6
    1 single yellow sock + 1 single yellow sock + 1 single yellow sock = 3 yellow socks.
     
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