If abc = b3 , which of the following must be true?
I. ac = b2
II. b = 0
III. ac = 1
A) None
B) I only
C) II only
D) I and III
E) II and III
This is from Kaplan CAT. I am not quite sure how they arrived at the answer.
OA is A
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If abc = b3 , which of the following must be true?
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Night reader
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does the problem specify b3 and not 3*b which is not possible with answer A (but still) may be b(+-)3, also division should be eliminated for answer A.
nikhilsrl wrote:If abc = b3 , which of the following must be true?
I. ac = b2
II. b = 0
III. ac = 1
A) None
B) I only
C) II only
D) I and III
E) II and III
This is from Kaplan CAT. I am not quite sure how they arrived at the answer.
OA is A
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stormier
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abc = b^3nikhilsrl wrote:If abc = b3 , which of the following must be true?
I. ac = b2
II. b = 0
III. ac = 1
A) None
B) I only
C) II only
D) I and III
E) II and III
This is from Kaplan CAT. I am not quite sure how they arrived at the answer.
OA is A
This is possible if either
b=0; or
ac = b^2
But none of the above individually must be true. Answer A
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Try to show that the answers don't have to be true.nikhilsrl wrote:If abc = b^3 , which of the following must be true?
I. ac = b^2
II. b = 0
III. ac = 1
A) None
B) I only
C) II only
D) I and III
E) II and III
This is from Kaplan CAT. I am not quite sure how they arrived at the answer.
OA is A
Let a = 2, b = 0, c = 2. This works, because 2*0*2 = 0^3.
I. ac = b^2
2*2 = 0^2.
Not true. Eliminate B and D, each of which includes I.
II. b = 0
True so far. Hold onto II.
III. ac = 1
2*2 = 1.
Not true. Eliminate E, which includes III.
Let a = 1, b = 1, c = 1, so that 1*1*1 = 1^3.
II. b = 0
Not true. Eliminate C.
The correct answer is A.
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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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