Are x and y both positive?
(1) 2x-2y=1
(2) x/y > 1
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statement(1):
x-y=1/2
Any combinations of (+,+),(+,-),(-,+),(-,-) are possible for x and y.
=> alone is not sufficient
statement(2):
x>y if y is positive else x<y
=> either both x and y are positive or both re negative
=> alone is not sufficient
statements taken together:
won't be sufficient as not resulting in a unique solution.
Answer "E"
x-y=1/2
Any combinations of (+,+),(+,-),(-,+),(-,-) are possible for x and y.
=> alone is not sufficient
statement(2):
x>y if y is positive else x<y
=> either both x and y are positive or both re negative
=> alone is not sufficient
statements taken together:
won't be sufficient as not resulting in a unique solution.
Answer "E"
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I agree (1) or (2) are INSUFFICIENT. but consider both of them together
(1) 2x-2y = 1
(2) x/y >1
Rephrasing (1)
x-y = 1/2
x = y + 1/2
Now substituting value of x in (2)
(y+1/2)/y >1
Solving:
1+ 1/2y > 1
so, 1/2y > 0 it means y >0 since x = y+1/2 s0 X >0 as well.
Hope it helps
(1) 2x-2y = 1
(2) x/y >1
Rephrasing (1)
x-y = 1/2
x = y + 1/2
Now substituting value of x in (2)
(y+1/2)/y >1
Solving:
1+ 1/2y > 1
so, 1/2y > 0 it means y >0 since x = y+1/2 s0 X >0 as well.
Hope it helps
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I agree with Mohitbhatia880's answer option "C". There is a flaw in my earlier explanation. We should not compare the ranges of statements (1) and (2), as I did in my earlier reply.If both the statements are considered, try to solve both the equations and get to a conclusion if possible. The ranges can't be compared but only the values from the two statements can be compared.
RaviSankar Vemuri
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https://mathbyvemuri.blogspot.in/2012/05 ... es-of.html
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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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