Is x a negative number?
(1) x2 is a positive number.
(2) x × |y| is not a positive number.
mgmat ds 2 700-800
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- pradeepkaushal9518
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- pradeepkaushal9518
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I presume x2 actually is x^2
x^2 is positive means, x is either +ve or -ve. Hence, insufficient.
x.|y| means, x into a positive number. Since it is given that the product is negative, it means that x must be negative. Hence [spoiler](B)[/spoiler].
x^2 is positive means, x is either +ve or -ve. Hence, insufficient.
x.|y| means, x into a positive number. Since it is given that the product is negative, it means that x must be negative. Hence [spoiler](B)[/spoiler].
- pradeepkaushal9518
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what if x*/y/ is zero then both x and Y will be zero
i m posting OE
(1) INSUFFICIENT: Since x2 is positive whether x is negative or positive, we can only determine that x is not equal to zero; x could be either positive or negative.
(2) INSUFFICIENT: By telling us that the expression x × |y| is not a positive number, we know that it must either be negative or zero. If the expression is negative, x must be negative (|y| is never negative). However if the expression is zero, x or y could be zero.
(1) AND (2) INSUFFICIENT: We know from statement 1 that x cannot be zero, however, there are still two possibilites for x: x could be positive (y is zero), or x could be negative (y is anything).
The correct answer is E.
i m posting OE
(1) INSUFFICIENT: Since x2 is positive whether x is negative or positive, we can only determine that x is not equal to zero; x could be either positive or negative.
(2) INSUFFICIENT: By telling us that the expression x × |y| is not a positive number, we know that it must either be negative or zero. If the expression is negative, x must be negative (|y| is never negative). However if the expression is zero, x or y could be zero.
(1) AND (2) INSUFFICIENT: We know from statement 1 that x cannot be zero, however, there are still two possibilites for x: x could be positive (y is zero), or x could be negative (y is anything).
The correct answer is E.
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The answer should be C
St-1 clearly not enough
St-2 says x * |y| is not positive ==> means either the product is -ve or it is 0 so, not enough
combining both ... enough
St-1 clearly not enough
St-2 says x * |y| is not positive ==> means either the product is -ve or it is 0 so, not enough
combining both ... enough
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Right!! Missed out the zero condition. Thankspradeepkaushal9518 wrote:what if x*/y/ is zero then both x and Y will be zero
The correct answer is E.