DS - Equations

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Source: — Data Sufficiency |

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Re: DS - Equations

by iamcste » Sat May 16, 2009 5:32 am
p2pg wrote:If 5w + 3v = 13, what is the value of vw ?

(1) w > 0

(2) W/V=2/1


OA - B
^


B gives you 2 linear distinct equations and you can solve for v and w to get vw

A

w=2, v=1 satisifes the qtn

while w=1/5, v=4 also satisifes the eqtn

since we dont have uniques value of v and w, we cannot have distinct values for vw

Choose B

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by p2pg » Sat May 16, 2009 5:38 am
Thanks for your reply. If "w" and "v" both are negative, then would still "B" be the answer. So I thought it to be E

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by p2pg » Sat May 16, 2009 5:40 am
Thanks for your reply. If "w" and "v" both are negative, then would still "B" be the answer. So I thought it to be E

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by awesomeusername » Mon May 18, 2009 1:52 pm
w and v could NOT both be negative because a negative number + a negative number is never a positive number. Therefore, you don't need to worry about this situation.
Constant dripping hollows out a stone.
-Lucretius