Hello,
Pls help me with the following DS question:
Is xy<0 ?
(1) 1/x<1/y
(2) 0<x
Thanks,
Molly
Pls help me with this DS question
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mollyrg wrote:Hello,
Pls help me with the following DS question:
Is xy<0 ?
(1) 1/x<1/y
(2) 0<x
Thanks,
Molly[/quotes
Is the answer C?
If so, then my reasoning is as follows:
1. 1/x<1/y THIS TELLS YOU NOTHING ABOUT THE SIGNS OF X AND Y
2. 0<x THIS TELLS US THAT X is POSITIVE
If you combine statement 2 with statement 1, the positive fraction 1/x < 1/y, hence Y must be positive as well
if both X and Y are positive then XY can't be less than 0