Absolute and Square Root-Gmat Prep test 1

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by amitansu » Mon May 26, 2008 10:36 pm
Thught D is ans here !!

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by getneonow » Mon May 26, 2008 10:38 pm
is E the right answer?? or was it ur bet??

i will go with B ...


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by ksh » Mon May 26, 2008 10:42 pm
If u solve the equation
(x-3)^2 =+-(3-x)
Stem1. Hence is NS
Stem2. NS

So, Ans is E

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by amitansu » Mon May 26, 2008 10:53 pm
I solved it like this :

From q itself : x-3=3-x=>x=3

From 1 : x not equal to 3 , so thought of yes or no and here it is no so sufficient.

From 2 : x has to be negative , but we already know x=3 i.e. positive.So sufficient !!

If E is ans , where i got wrong ?

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by khurram » Tue May 27, 2008 6:25 am
Ans is B.

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by khurram » Tue May 27, 2008 6:30 am
Still confused about this one. Sorry I had E Ans for this one before.

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by AleksandrM » Tue May 27, 2008 9:32 am
THe first statement says that x does not equal to 3. This means it could be positive or negative, which will give you numbers for which the answer will be yes and those for which the answer will be no.

Statement two says that when you take the absolute value of x and then multiply it by negative of x, you will get an answer greater than zero. This can only be true if x is negative. For example:

-(-3)|-3| > 0

Take any negative number, and you will satisfy the equation. Answer will be yes. X can be ANY negative number, fraction or integer.

Choose B.

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by khurram » Tue May 27, 2008 11:34 am
starting to make sense.

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by netigen » Tue May 27, 2008 12:00 pm
this question can be rephrased as

is |x-3| = 3-x ?

quick check tells us that when x<=3 this eq holds but when x>3 this eq does not hold

(A) is no help

(B) tell me that x<0 hence for all x the eq above will hold

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by pranavc » Tue May 27, 2008 5:02 pm
I still don't get it. Solving the equation suggests that the only way the left hand side will be equal to the right hand side is when x=3. Statement 1 indicates that 'x' is NOT equal to 3. Which means, it should be obvious that the left hand side and right hand side are equal. Doesn't that make this statement sufficient in itself?

With statement B, it indicates that x has to be negative which it cannot be for the two sides to be equal. Hence, it appears that both statement in themselves should be sufficient. Doesn't that lead D to be the answer. PLease clarify. Thanks in advance.

Regards,

Pranav