3) Is it true that a > b ?
(1) a2 > b2
(2) a > b - 2
E
[Moderator Edit: Moving the post to DS section : neelgandham]
practice inequality
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Target question: Is a > b ?sana.noor wrote:3) Is it true that a > b ?
(1) a^2 > b^2
(2) a > b - 2
Statement 1: a^2 > b^2
There are several pairs of values that meet this condition. Here are two:
Case a: a = 1 and b = 0, in which case a is greater than b
Case b: a = -1 and b = 0, in which case a is not greater than b
Since we cannot answer the target question with certainty, statement 1 is NOT SUFFICIENT
Statement 2: a > b - 2
There are several pairs of values that meet this condition. Here are two:
Case a: a = 1 and b = 0, in which case a is greater than b
Case b: a = -1 and b = 0, in which case a is not greater than b
Since we cannot answer the target question with certainty, statement 2 is NOT SUFFICIENT
Statements 1 and 2 combined:
There are still several pairs of values that meet this condition. Here are two:
Case a: a = 1 and b = 0, in which case a is greater than b
Case b: a = -1 and b = 0, in which case a is not greater than b
Since we still cannot answer the target question with certainty, the combined statements are NOT SUFFICIENT
Answer = E
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Question stem, rephrased: Is a-b > 0?sana.noor wrote:3) Is it true that a > b ?
(1) a2 > b2
(2) a > b - 2
E
Statement 1, rephrased:
a² - b² > 0
(a+b)(a-b) > 0.
Statement 2, rephrased:
a-b > -2.
Both statements are satisfied if a+b = 1 and a-b = 3, in which case a-b > 0.
Both statements are satisfied if a+b = -3 and a-b = -1, in which case a-b < 0.
Thus, the two statements combined are INSUFFICIENT.
The correct answer is E.
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Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
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