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Is xy < 0 ? [#permalink]
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08 May 2012, 03:25
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Re: Is xy < 0 ? [#permalink]
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08 May 2012, 09:34
Statement 1 => x = y = 0. Sufficient. Statement 2 => x = y = 0. Sufficient. Choice D.
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Re: Is xy < 0 ? [#permalink]
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08 May 2012, 12:44
GyanOne wrote: Statement 1 => y/x = 5 => x and y are of opposite signs => xy<0. Sufficient. Statement 2 => x/y = 5 => x and y are of opposite signs => xy<0. Sufficient.
Choice D. D as well, but think about it  (1) 5x + y = 0 When is a sum equal to zero? one is negative, one is positive. But  (absolute value?, not sure what is the English for it) can't be negative, thus both x an y should be equal to zero. This means xy clearly is not < 0, but equal to zero. Sufficient (2) same thing for this option



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Re: Is xy < 0 ? [#permalink]
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09 May 2012, 02:42
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Re: Is xy < 0 ? [#permalink]
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23 Sep 2014, 15:18
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Re: Is xy < 0 ? [#permalink]
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26 Sep 2014, 14:12
question is X and y are opposite sign?
stmt 1 : 5x=y x/y =  5, x and y are opposite sign , sufficient.
stmt2L x=5y, x/y = 5 , x and y are opposite sign , sufficient.
if x and y are same sign x/y will always be positive.



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Re: Is xy < 0 ? [#permalink]
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Re: Is xy < 0 ? [#permalink]
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13 Mar 2016, 22:24
Forget conventional ways of solving math questions. In DS, Variable approach is the easiest and quickest way to find the answer without actually solving the problem. Remember equal number of variables and independent equations ensures a solution. Is xy < 0? In the original condition, there are 2 variables(x,y), which should match with the number of equations. So you need 2 equations. For 1) 1 equation, for 2) 1 equation, which is likely to make C the answer. When 1) & 2), 1)=2) > x=y=0, which is no and sufficient. Thus, D is the answer. For cases where we need 2 more equations, such as original conditions with “2 variables”, or “3 variables and 1 equation”, or “4 variables and 2 equations”, we have 1 equation each in both 1) and 2). Therefore, there is 70% chance that C is the answer, while E has 25% chance. These two are the majority. In case of common mistake type 3,4, the answer may be from A, B or D but there is only 5% chance. Since C is most likely to be the answer using 1) and 2) separately according to DS definition (It saves us time). Obviously there may be cases where the answer is A, B, D or E.
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Is xy < 0? [#permalink]
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25 Mar 2017, 23:29
Is xy < 0? 1. 5x + y = 0 2. x + 5y = 0
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Re: Is xy < 0? [#permalink]
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25 Mar 2017, 23:31
No, it is equal to 0
Enviado desde mi LGD855 mediante Tapatalk



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Re: Is xy < 0? [#permalink]
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26 Mar 2017, 04:26
ashwink wrote: Is xy < 0?
1. 5x + y = 0 2. x + 5y = 0 But where are the possible answers?



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Re: Is xy < 0 ? [#permalink]
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26 Mar 2017, 04:44



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Re: Is xy < 0 ? [#permalink]
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26 Mar 2017, 04:46
RodrigoPerant wrote: ashwink wrote: Is xy < 0?
1. 5x + y = 0 2. x + 5y = 0 But where are the possible answers? This is a data sufficiency question. Options for DS questions are always the same. The data sufficiency problem consists of a question and two statements, labeled (1) and (2), in which certain data are given. You have to decide whether the data given in the statements are sufficient for answering the question. Using the data given in the statements, plus your knowledge of mathematics and everyday facts (such as the number of days in July or the meaning of the word counterclockwise), you must indicate whether— A. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient to answer the question asked. B. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient to answer the question asked. C. BOTH statements (1) and (2) TOGETHER are sufficient to answer the question asked, but NEITHER statement ALONE is sufficient to answer the question asked. D. EACH statement ALONE is sufficient to answer the question asked. E. Statements (1) and (2) TOGETHER are NOT sufficient to answer the question asked, and additional data specific to the problem are needed. I suggest you to go through the following post ALL YOU NEED FOR QUANT. Hope this helps. P.S. You can check the OA (Official Answer) under the spoiler in the original post.
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Re: Is xy < 0 ? [#permalink]
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26 Mar 2017, 05:06
Bunuel wrote: RodrigoPerant wrote: ashwink wrote: Is xy < 0?
1. 5x + y = 0 2. x + 5y = 0 But where are the possible answers? This is a data sufficiency question. Options for DS questions are always the same. The data sufficiency problem consists of a question and two statements, labeled (1) and (2), in which certain data are given. You have to decide whether the data given in the statements are sufficient for answering the question. Using the data given in the statements, plus your knowledge of mathematics and everyday facts (such as the number of days in July or the meaning of the word counterclockwise), you must indicate whether— A. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient to answer the question asked. B. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient to answer the question asked. C. BOTH statements (1) and (2) TOGETHER are sufficient to answer the question asked, but NEITHER statement ALONE is sufficient to answer the question asked. D. EACH statement ALONE is sufficient to answer the question asked. E. Statements (1) and (2) TOGETHER are NOT sufficient to answer the question asked, and additional data specific to the problem are needed. I suggest you to go through the following post ALL YOU NEED FOR QUANT. Hope this helps. P.S. You can check the OA (Official Answer) under the spoiler in the original post. Oh that is why! Thank you so much for your explanation Enviado desde mi LGD855 mediante Tapatalk











