XY

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Source: — Data Sufficiency |

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by amitabhprasad » Thu Dec 18, 2008 8:01 pm
I am getting "E"
qstn stem y-x>0
stmt 1 : y >0 no info abt x not sufficient
stmt 2 : x+y = 1 pick a number say x= y =1/2
satisfies statement but y - x = 0
now say y = 3 but x = -2 ==> y-x = 5 so not sufficient
if you combine 1 and 2 it will result in same as statement 2
so I will go with "E"

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Re: XY

by logitech » Thu Dec 18, 2008 8:03 pm
sogmat wrote:Is y – x positive?
(1) y > 0
(2) x = 1 - y
Is y-x>0 actually means Is y>x ?

1)Insuf we dont know anything about x
2)x+y = 1 but we dont know whether y>x

y>1-y

2y>1

y>1/2

so y-x is positive only if y is greater than 1/2

Question stem does not give us any information such as Y or X is integer

INSUF

st1+2

we still dont know whether y is greater than 1/2

so I would choose E
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by pbanavara » Thu Dec 18, 2008 8:35 pm
Since we don't know whether x and y are integers - it's E .. rest of the reasoning same as the ones given above.

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