If a/b<c/d & bd < 0, which of the following inequalities must be true?
I. ad -bc < 0
II. bc -ad > 0
III. ad -bc > 0
A. I only
B. II only
C. III only
D. I and II
E. II and III
OA C
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If a/b<c/d & bd < 0, which of the following inequa
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BTGmoderatorDC
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In I, II and III, test the following case:BTGmoderatorDC wrote:If a/b < c/d & bd < 0, which of the following inequalities must be true?
I. ad -bc < 0
II. bc -ad > 0
III. ad -bc > 0
A. I only
B. II only
C. III only
D. I and II
E. II and III
a=c=d=1 and b=-1, with the result that a/b < c/d and bd < 0.
I: ad-bc < 0
Since ad=1*1=1 and bc=-1*1=-1, we get:
1 - (-1) < 0
2 < 0
Not true.
Eliminate A and D, each of which include I.
II: bc-ad > 0
Since bc=-1*1=-1 abd ad=1*1=1, we get:
-1 - 1 > 0
-2 > 0
Not true.
Eliminate B and E, each of which include II.
The correct answer is C.
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Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
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