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        riddles >> hard >> Hard- Mastermind2, Vanishing Dollar
        
(Message started by: Cze-Jwin on Jul 24^th, 2002, 3:22am)

Title: Hard- Mastermind2, Vanishing Dollar
Post by Cze-Jwin on Jul 24^th, 2002, 3:22am

mastermind2
yellow, yellow, yellow, light blue

vanishing dollar

hmm..hope this is a satisfactory answer...

each man gives 10, therefore hotel has 30
subtract 5 from hotel...hotel has 25 profit
give back to men 1
bellboy takes 2

men technically give 9 each, total is 27
of the 27 bellboy took 2, so its 25

thats how much hotel got from men is 25

Title: Re: Hard- Mastermind2, Vanishing Dollar
Post by cnmne on Jul 27^th, 2002, 11:56am

vanishing dollar:

the problem misleads by saying 27+2 = 29, which is true but does not relate to the problem. 27-2 = 25 is also true, and relates to the problem.

Title: Mastermind2
Post by NoJoy on Aug 9^th, 2002, 12:31pm

A little analysis of the previously posted solution:
a. There is only one color change from (1) to (2), but the
number of black and white pegs goes up by 1. This means
that the newly added color, yellow, is present in A's
arrangement.
b. There is a yellow peg in (3), and there are no white pegs,
so the yellow peg is in the third position in A's arrangement.
c. Suppose the yellow peg in (4) accounts for the white peg.
No colors are removed from (3) to (4), so it is a cyan or
green peg, rather than the brown peg, which accounts for
the black peg in (4). It also contributed a black peg in (3),
so it is the green peg in the second position. But the
conclusion that the green peg is in the second position
and the yellow peg is in the third position is inconsistent
with the black and white pegs in (2). Hence the
assumption that the yellow peg accounts for the white
peg is false.
d. A yellow peg must be present, and it does not account for
the white peg, hence it accounts for the black peg, and
hence is in the first position.
e. Because the yellow peg accounts for the black peg in (4),
neither green peg in (3) can account for the second black
peg in (3), so the cyan peg accounts for the second black
peg, and hence is in the fourth position.
f. The cyan peg accounts for the white peg in (1), so there
are no green, blue, or red pegs in A's arrangement. Hence
the yellow peg in (2) accounts for the black peg, and
hence is in the second position.
g. Thus A's arrangement is yellow, yellow, yellow, cyan.

Title: Re: Hard- Mastermind2, Vanishing Dollar
Post by Robert Grimsley on Aug 23^rd, 2002, 1:36pm

The vanishing dollar quiz is 'hard'? This is one of the easiest on the web page. Lots of the 'easy' quizzes are harder than this one. (See answer above, if you didn't figure it out yourself.)

Title: Re: Hard- Mastermind2, Vanishing Dollar
Post by Brad711 on Dec 13^th, 2004, 4:27pm

This is hard?!? I had this in my Elementary Algebra class. Well, I'm still in my Elementary Algebra class, and still only in 7th grade 8)!!! There is no missing dollar! $29 has nothing to do with the problem. The problem is (3*9) for the 3 guys and the busboy took 2, thus the hotel has (3*9)-2=25. This is an easy problem.