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Slashpuzzler

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Posts posted by Slashpuzzler


  1. Ok , NOW  I got it ,

    Spoiler

    8 mins  is the fastest
    lets consider fast rower as r  , and slower as s ,    and   | |   be the bridge 
    sssrr  |  |                                     0 min
     sss     |  |    rr                             1 min
     sssr   |  |   r                                2 min
           r    |  |    sssr                        6 min
          rr   |  |   sss                           7 min 
                |  |   sssrr                        8 min

     


  2. I think I got it ....

    Spoiler

    Using a rubics cube   ;)  , and using rotational symmetry to simplify counting I get,

    C- core   ,    M - middle or face ,    E - edge,     R-  as in corner.

    CM- 1         MM -2         EE - 5   
    CE  -1         ME  -3         ER  -4
    CR -1          MR -2          RR -3
           3    +            7      +       12        =    22 ways  

     


  3. Not sure if my method is the right way to do it...

    Spoiler

    Now , we can only choose a core , corner , edge or the middle piece from all the pieces.
    I made a table where I took 1 piece , and then check the no of ways I can take the second piece.
                                                      corner                edge                 center               core
                           core                       1                          1                        1                        X                 = 3 ways
                           corner                  3                           3                       2                         X                 =8 ways
                           edge                     X                           4                       3                         X                 = 7 ways
                           center                  X                           X                       2                         X            =    2 ways
    X is marked for spots that are already counted .
    So , total distinct no of shapes =  3+8+7+2 = 20 ways

     


  4. After the chamber is spun , the bullet can only occupy 6 positions .

    Spoiler

     

    And in going through all the positions :

    1. bullet in 1st position -- 1st guy loses
    2. bullet in 2nd position -- 2nd guy loses
    3. bullet in 3rd position -- 3rd guy loses 
    4. bullet in 4th position -- 4th guy loses
    5. bullet in 5th position -- 5th guy loses 
    6. bullet in 6th position -- 1st guy loses

    And since these are all the possibilities that can happen and there are no other possible outcomes , 
    the position at 2nd , 3rd , 4th and 5th are the safest with 1/6 chance of lossing .
    This is pretty much it I guess.... tell me if I am wrong.

     

     

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