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x#y function problem

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x#y function problem

by pappueshwar » Sun Feb 05, 2012 3:10 am
If x#y = 2x-y where x is not equal to 2y then is a#b > b#a
--------
2y-x

1) a < b
2) 2a < b

request to explain this problem in a simple way if possible as i completely at loss to how to do this
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by bryan88 » Sun Feb 05, 2012 10:38 am
a#b=2a-b
b#a=2b-a

Is a#b>b#a
Is 2a-b>2b-a
Is(a-b)>0

IMO A
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by tpr-becky » Tue Feb 07, 2012 12:38 pm
you can rewrite the question 2a-b>2b-a

you can manipulate that to 3a>3b and divide both sides by three to get the real question to be is a>b?

Statement 1 says that a is in fact less than b therefore a can never be greater than b which means this is a sufficient answer because we can always answer that a >b. Leave A/D.

Statement 2 says that 2a<b - this is even stronger than the first in that we know that a <1/5b so a will always be less than b. Thus this is sufficient again and the answer is D.
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by kris610 » Tue Feb 07, 2012 6:42 pm
Does the question say x#y = (2x-y/2y-x)?
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by tpr-becky » Tue Feb 07, 2012 6:52 pm
It says the first but when you put in the a and b it is just about first number, second number so the equation says 2(first nubmer) - second number.
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