Is x<y ?
(1) 2x < 3y
(2) xy > 0
I really thought this one would be C (both would answer the question), but the key says it's E.
Any thoughts as to why?
Is X < Y ?
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Please repost and click the "disable HTML in this post" box below.adi wrote:Is x<y ?
(1) 2x <3y> 0
I really thought this one would be C (both would answer the question), but the key says it's E.
Any thoughts as to why?
Stuart Kovinsky | Kaplan GMAT Faculty | Toronto
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- Stuart@KaplanGMAT
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Whenever inequalities are involved, we want to focus on the signs of the variables.adi wrote:Is x<y ?
(1) 2x < 3y
(2) xy > 0
I really thought this one would be C (both would answer the question), but the key says it's E.
Any thoughts as to why?
(1) 2x < 3y
or
x < (3/2)y
Does this tell us if x is less than y?
Nope, we could pick x=1 and y=50 to get a "yes" answer or we could pick x = 1.1 and y = 1 to get "no" answer: insufficient.
(2) xy > 0
This tells us that x and y are both positive or both negative, but nothing about the values: insufficient.
When we combine the statements, we can still get both a "yes" and a "no", since both sets of numbers from statement (1) could still be used.
Choose (E).
Stuart Kovinsky | Kaplan GMAT Faculty | Toronto
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