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Source: — Data Sufficiency |

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by cramya » Fri Feb 13, 2009 5:25 pm
To find

k-x+k-y+k-w = 3k - (x+y+w)

Stmt I

x,y,w three consecutive odd intgers. Could be anything and we still dont know what k is

INSUFF

Stmt II

x+y+w/3 = 3

x+y+w=9

INSUFF

Together the three numbers ar 1,3,5 but still no idea on k

I would choose E and must be missing something if its B

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by AJ2009 » Fri Feb 13, 2009 6:47 pm
I also thin it is E, don't see where the value of K could come from.

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by jackcrystal » Fri Feb 13, 2009 10:28 pm
it got to be - E

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by Uri » Sat Feb 14, 2009 3:31 am
there is no way that we can find the value of this equation without knowing "k". IMHO (E)
could you please specify the source of this problem?

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by awesomeusername » Sat Feb 14, 2009 9:22 am
I also got the same thing. We can solve for all variables but k.

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by MJ23 » Tue Jun 14, 2011 5:02 pm
(1) insufficient can be any numbers

(2) (w+x+y)/3 = k
3k = w+x+y

if we rearange the formula in the questions it reads as 3k - (w+x+y)
substitute and you get (w+x+y) - (w+x+y)

2 is sufficient therefore answer is B

is this correct? it makes sense if the average of the three variables is K and the three variables are getting subtracted from K and added together, it should net out to 0

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by Ian Stewart » Tue Jun 14, 2011 6:27 pm
MJ23 wrote:(1) insufficient can be any numbers

(2) (w+x+y)/3 = k
3k = w+x+y

if we rearange the formula in the questions it reads as 3k - (w+x+y)
substitute and you get (w+x+y) - (w+x+y)

2 is sufficient therefore answer is B

is this correct? it makes sense if the average of the three variables is K and the three variables are getting subtracted from K and added together, it should net out to 0
I guess you've changed statement 2 here to "the mean of w, x and y is k" instead of "the mean of w, x and y is 3" (as it was written in the original post above). With that change, the answer is certainly B, as you've shown. Since the OA is B, I'm guessing there was either a typo in the original post or in the source of the question, and I think your suggested rewrite is what the question was intended to be. It is certainly a more interesting question that way, since when Statement 2 reads as it does in the original post, it's pretty obvious that the answer is E, since we have no information about k and we need information about k.
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