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If xyz < 0 and z < 0, then which of the following must be tr
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02 Apr 2020, 08:02
02 Apr 2020, 08:02
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If \(xyz < 0\) and \(z < 0\), then which of the following must be true?
A. \(xy=1\)
B. \(xy<1\)
C. \(xy>-z\)
D. \(zy<z\)
E. \(xy>0\)
Kudos for the right answer and explanation
A. \(xy=1\)
B. \(xy<1\)
C. \(xy>-z\)
D. \(zy<z\)
E. \(xy>0\)
Kudos for the right answer and explanation
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Re: If xyz < 0 and z < 0, then which of the following must be tr
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02 Apr 2020, 09:29
02 Apr 2020, 09:29
Carcass wrote:
If \(xyz < 0\) and \(z < 0\), then which of the following must be true?
A. \(xy=1\)
B. \(xy<1\)
C. \(xy>-z\)
D. \(zy<z\)
E. \(xy>0\)
Kudos for the right answer and explanation
A. \(xy=1\)
B. \(xy<1\)
C. \(xy>-z\)
D. \(zy<z\)
E. \(xy>0\)
Kudos for the right answer and explanation
One approach....
Given: xyz is NEGATIVE and z is NEGATIVE
We know that xyz = (xy)(z)
Replace values to get: NEGATIVE = (xy)(NEGATIVE)
From this we can conclude that (xy) is POSITIVE
Answer: E
Cheers,
Brent
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Schools: XLRI Jamshedpur, India - Class of 2014
GMAT 1: 700 Q51 V31
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WE:Engineering (Computer Software)
Re: If xyz < 0 and z < 0, then which of the following must be tr
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28 Dec 2021, 02:21
28 Dec 2021, 02:21
1
Given that \(xyz < 0\) and \(z < 0\)
Now, xyz < 0 and z < 0
=> (xy) * z < 0
Now product of two numbers xy and z is < 0 and we know that
Product of two numbers is negative => one number is negative and other is positive.
Now, we already know that z < 0 (negative)
=> xy has to be positive
=> xy > 0
So, Answer will be E
Hope it helps!
Watch the following video to learn the Basics of Inequalities
Now, xyz < 0 and z < 0
=> (xy) * z < 0
Now product of two numbers xy and z is < 0 and we know that
Product of two numbers is negative => one number is negative and other is positive.
Now, we already know that z < 0 (negative)
=> xy has to be positive
=> xy > 0
So, Answer will be E
Hope it helps!
Watch the following video to learn the Basics of Inequalities
