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        riddles >> easy >> Question Mark and his brother
        
(Message started by: BenVitale on Jun 21^st, 2009, 10:41pm)

Title: Question Mark and his brother
Post by BenVitale on Jun 21^st, 2009, 10:41pm

After recent events, Question Mark is annoyed with his brother, Skid Mark. Skid thought it would be funny to hide Question's wallet. He told Question that he would get it back if he finds it. So, first off, Skid laid five colored keys in a row. One of them is a key to a room where Skid is hiding Question's wallet. Using the clues, can you determine the order of the keys and which is the right key?

Red: This key is somewhere to the left of the key to the door.
Blue: This key is not at one of the ends.
Green: This key is three spaces away from the key to the door (2 between)
Yellow: This key is next to the key to the door.
Orange: This key is in the middle.

Title: Re: Question Mark and his brother
Post by Grimbal on Jun 22^nd, 2009, 1:05am

Yes, [hide] I can! [/hide]

Title: Re: Question Mark and his brother
Post by gotit on Jun 22^nd, 2009, 1:48am

[hide]Me too[/hide] 8)

Title: Re: Question Mark and his brother
Post by Ronno on Jun 22^nd, 2009, 6:11am

[hide]Blue[/hide]?

Title: Re: Question Mark and his brother
Post by Grimbal on Jun 22^nd, 2009, 6:16am

I got the same.

Title: Re: Question Mark and his brother
Post by MathsForFun on Jun 22^nd, 2009, 6:30am

The following LP_Solve integer linear programming model produces a solution that meets all of the criteria given:

[hideb]/* Objective function */
min: ;
red1 + red2 + red3 + red4 + red5 = 1;
blue1 + blue2 + blue3 + blue4 + blue5 = 1;
green1 + green2 + green3 + green4 + green5 = 1;
yell1 + yell2 + yell3 + yell4 + yell5 = 1;
orange1 + orange2 + orange3 + orange4 + orange5 = 1;
door1 + door2 + door3 + door4 + door5 = 1;
red1 + blue1 + green1 + yell1 + orange1 = 1;
red2 + blue2 + green2 + yell2 + orange2 = 1;
red3 + blue3 + green3 + yell3 + orange3 = 1;
red4 + blue4 + green4 + yell4 + orange4 = 1;
red5 + blue5 + green5 + yell5 + orange5 = 1;
red2 + door2 + door1 <= 1;
red3 + door1 + door2 + door3 <= 1;
red4 + door1 + door2 + door3 + door4 <= 1;
red5 + door1 = 0;
blue1 + blue5 = 0;
green3 + door3 = 0;
green1 - door4 = 0;
green2 - door5 = 0;
green4 - door1 = 0;
green5 - door2 = 0;
yell1 - door2 <= 0;
yell5 - door4 <= 0;
yell2 - door1 - door3 <= 0;
yell3 - door2 - door4 <= 0;
yell4 - door3 - door5 <= 0;
lbl1: orange3 = 1;
bin red1 red2 red3 red4 red5 blue1 blue2 blue3 blue4 blue5 green1 green2 green3 green4 green5 yell1 yell2 yell3 yell4 yell5 orange1 orange2 orange3 orange4 orange5 door1 door2 door3 door4 door5;[/hideb]

Title: Re: Question Mark and his brother
Post by gotit on Jun 22^nd, 2009, 8:18am

Does it really ask for so much??

It obviously cannot be the red, green or yellow one. It cannot be the orange one since it is at the center and the green is 3 spaces away from the required key.

Title: Re: Question Mark and his brother
Post by rmsgrey on Jun 23^rd, 2009, 9:47am

And it doesn't take much more to figure out the correct order of the keys: [hide]GROBY[/hide]

Reasoning:
[hideb]
Orange is at the center _ _ O _ _
Blue (the right key) is not at either end, so Green, three spaces from it is at the opposite end: G_OB_ or _BO_G
Yellow is next to Blue: G_OBY or YBO_G and Red is to the left of Blue: GROBY
[/hideb]

Title: Re: Question Mark and his brother
Post by chronodekar on Jun 25^th, 2009, 4:15am

[hide]Thats what I got too. Blue the 4th from the left.[/hide]

-chronodekar