r u missing something here?dtweah wrote:Suppose A, B, C, D are positive integers such that exactly one of the following inequalities is false. Which inequality is False?
A. A<B
B. C< D
C. A+ C < B+C
D. A+C< B+ D
E. A< B+C+D
Inequality
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maihuna
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Charged up again to beat the beast 
maihuna wrote:Nothing.dtweah wrote:Suppose A, B, C, D are positive integers such that exactly one of the following inequalities is false. Which inequality is False?
A. A<B
B. C< D
C. A+ C < B+C
D. A+C< B+ D
E. A< B+C+D
r u missing something here?
A and C are the same, so discarded. Since we're dealing with positive numbers, A implies E, so E discarded.
Now, we're left with B and D. If B is true, D must also be true, and thus all inequalities would be true, contradicting the requirement ==> B is false.
Answer is B
Now, we're left with B and D. If B is true, D must also be true, and thus all inequalities would be true, contradicting the requirement ==> B is false.
Answer is B
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lunarpower
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the above solution is valid, yes.
this is an extremely clever problem; in fact, i like it quite a bit. however, i'm afraid it's not at all like anything i've ever seen in an official problem.
not at all like anything.
this is more like the sort of thing that would show up on a junior-high or high school Math Olympiad for gifted kids. if there's a standardized-test connection, i'd say that this problem bears some resemblance to the "logic games" problems that show up on the LSAT, except it's been hammered into the shape of a math problem.
in any case, it's far too formal-logic-heavy and "proof"-like to be a legitimate candidate for a gmat problem.
where'd you get it?
this is an extremely clever problem; in fact, i like it quite a bit. however, i'm afraid it's not at all like anything i've ever seen in an official problem.
not at all like anything.
this is more like the sort of thing that would show up on a junior-high or high school Math Olympiad for gifted kids. if there's a standardized-test connection, i'd say that this problem bears some resemblance to the "logic games" problems that show up on the LSAT, except it's been hammered into the shape of a math problem.
in any case, it's far too formal-logic-heavy and "proof"-like to be a legitimate candidate for a gmat problem.
where'd you get it?
Ron has been teaching various standardized tests for 20 years.
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Pueden hacerle preguntas a Ron en castellano
Potete chiedere domande a Ron in italiano
On peut poser des questions à Ron en français
Voit esittää kysymyksiä Ron:lle myös suomeksi
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Quand on se sent bien dans un vêtement, tout peut arriver. Un bon vêtement, c'est un passeport pour le bonheur.
Yves Saint-Laurent
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Learn more about ron
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lunarpower
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you won't. see my post above.Vemuri wrote:I hope I don't see such a question on the D day
this is just not the style of the questions that show up on the test.
Ron has been teaching various standardized tests for 20 years.
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Pueden hacerle preguntas a Ron en castellano
Potete chiedere domande a Ron in italiano
On peut poser des questions à Ron en français
Voit esittää kysymyksiä Ron:lle myös suomeksi
--
Quand on se sent bien dans un vêtement, tout peut arriver. Un bon vêtement, c'est un passeport pour le bonheur.
Yves Saint-Laurent
--
Learn more about ron
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Pueden hacerle preguntas a Ron en castellano
Potete chiedere domande a Ron in italiano
On peut poser des questions à Ron en français
Voit esittää kysymyksiä Ron:lle myös suomeksi
--
Quand on se sent bien dans un vêtement, tout peut arriver. Un bon vêtement, c'est un passeport pour le bonheur.
Yves Saint-Laurent
--
Learn more about ron
