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nidhis.1408
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It seems something is missing!
Whats the source of all these questions?
data sufficiency problem
This topic has expert replies
Source: Beat The GMAT — Problem Solving |
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nidhis.1408
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i am sorry. i just copy pasted d question and didnt realise that there "to the power" is wrong.
this is the correct question
If A = 2B, is A^4 > B^4?
(1) A^2 = 4B^2.
(2) 2A + B < A/2 + B.
(a) Statement (1) BY ITSELF is sufficient to answer the question, but statement (2) by itself is not.
(b) Statement (2) BY ITSELF is sufficient to answer the question, but statement (1) by itself is not.
(c) Statements (1) and (2) TAKEN TOGETHER are sufficient to answer the question, even though NEITHER statement BY ITSELF is sufficient.
(d) Either statement BY ITSELF is sufficient to answer the question.
(e) Statements (1) and (2) TAKEN TOGETHER are NOT sufficient to answer the question, requiring more data pertaining to the problem.
BTW source of the question is
https://www.hp-vietnam.com/GMAT-Practice-Test-1-Math.asp
this is the correct question
If A = 2B, is A^4 > B^4?
(1) A^2 = 4B^2.
(2) 2A + B < A/2 + B.
(a) Statement (1) BY ITSELF is sufficient to answer the question, but statement (2) by itself is not.
(b) Statement (2) BY ITSELF is sufficient to answer the question, but statement (1) by itself is not.
(c) Statements (1) and (2) TAKEN TOGETHER are sufficient to answer the question, even though NEITHER statement BY ITSELF is sufficient.
(d) Either statement BY ITSELF is sufficient to answer the question.
(e) Statements (1) and (2) TAKEN TOGETHER are NOT sufficient to answer the question, requiring more data pertaining to the problem.
BTW source of the question is
https://www.hp-vietnam.com/GMAT-Practice-Test-1-Math.asp
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shankar.ashwin
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Given, A=2B , For finding A^4 > B^4? we need to know is A is +ve or -ve.
(1) A^2 = 4B^2. We cannot determine signs of A,B (Insuff)
(2) 2A + B < A/2 + B = 3/2 A < 0 (or) A<0.
We know A is -ve. B will also be -ve and a smaller number. Sufficient. B IMO
(1) A^2 = 4B^2. We cannot determine signs of A,B (Insuff)
(2) 2A + B < A/2 + B = 3/2 A < 0 (or) A<0.
We know A is -ve. B will also be -ve and a smaller number. Sufficient. B IMO
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user123321
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1) fails when A=0 and obeys above condition for rest of the values
hence not sufficient
2) after solving becomes A<0 => B<0
so always (2B)^4>B^4 because it eliminates the possibility of either of them becoming zero. hence sufficient.
user123321
hence not sufficient
2) after solving becomes A<0 => B<0
so always (2B)^4>B^4 because it eliminates the possibility of either of them becoming zero. hence sufficient.
user123321
Just started my preparation 
Want to do it right the first time.
Want to do it right the first time.
