Inequality

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Inequality

by jainrahul1985 » Sat Jul 25, 2009 9:30 pm
Q7:
If y is an integer and y = |x| + x, is y = 0?
(1) x < 0
(2) y < 1
A. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
B. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
C. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is
sufficient.
D. EACH statement ALONE is sufficient.
E. Statements (1) and (2) TOGETHER are NOT sufficient.
Source: — Problem Solving |

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by shibal » Sun Jul 26, 2009 5:22 am
IMO A
OA?

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by aksravs » Sun Jul 26, 2009 5:28 am
x is -ve
y = x+(-x) = 0
hence stmt1 sufficient.

y<1
is not sufficient.

Hence A

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by jainrahul1985 » Sun Jul 26, 2009 5:37 am
Answer is D . I am not sure whether it is correct . Can someone look at this question once again

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by Ian Stewart » Sun Jul 26, 2009 6:22 am
y = x + |x| = 0 if x is negative or zero

y = x + |x| = 2x if x is positive

Notice that y > 0 no matter what x is. So if y < 1, and y is an integer, y must be zero, and S2 is sufficient. And if x < 0, we know that y = 0 from the above, so S1 is sufficient.
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