It is currently 21 Oct 2017, 09:06

GMAT Club Daily Prep

Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

If A=BC, is A>B ?

Author Message
TAGS:

Hide Tags

Senior Manager
Joined: 10 Apr 2012
Posts: 277

Kudos [?]: 1155 [0], given: 325

Location: United States
Concentration: Technology, Other
GPA: 2.44
WE: Project Management (Telecommunications)
If A=BC, is A>B ? [#permalink]

Show Tags

28 Jan 2013, 02:30
2
This post was
BOOKMARKED
00:00

Difficulty:

35% (medium)

Question Stats:

70% (01:02) correct 30% (01:03) wrong based on 61 sessions

HideShow timer Statistics

If A=BC, is A>B ?

(1) 0<C<1
(2) A>0

[Reveal] Spoiler:
Isn't B alone sufficient to answer the question ?

Appreciate if some one could explain ..
[Reveal] Spoiler: OA

Last edited by Bunuel on 28 Jan 2013, 02:40, edited 1 time in total.
Renamed the topic, edited the question and moved to SS forum.

Kudos [?]: 1155 [0], given: 325

Math Expert
Joined: 02 Sep 2009
Posts: 41892

Kudos [?]: 129111 [1], given: 12194

Re: If A=BC, is A>B ? [#permalink]

Show Tags

28 Jan 2013, 03:04
1
KUDOS
Expert's post
If A=BC, is A>B ?

Since A=BC, then the question can be re-written as "is BC>B?" --> is B(C-1)>0? Basically the question asks whether B and C-1 have the same sign.

(1) 0<C<1 --> C-1<0. We don't know the sign of B. Not sufficient.

For example, if A=1/4 and B=C=1/2, then A<B but if A=-1/2, B=-1 and C=1/2, then A>B. Not sufficient.

(2) A>0. If A=B=C=1, then A=B but if A=1 and B=C=-1, then A>B. Not sufficient.

(1)+(2) From above we have that both A and C are positive, hence B must also be positive (from A=BC). So, we have that B>0 and C-1<0: B and C-1 have opposite signs, therefore B(C-1)<0 (we have a definite NO answer to the question). Sufficient.

P.S. Please read carefully and follow: rules-for-posting-please-read-this-before-posting-133935.html Pay attention to the rules #1 (Choose the Right Forum) and #3 (the name of a topic (subject field) MUST be the first 40 characters (~the first two sentences) of the question).
_________________

Kudos [?]: 129111 [1], given: 12194

VP
Status: Been a long time guys...
Joined: 03 Feb 2011
Posts: 1377

Kudos [?]: 1679 [1], given: 62

Location: United States (NY)
Concentration: Finance, Marketing
GPA: 3.75
Re: If A=BC, is A>B ? [#permalink]

Show Tags

28 Jan 2013, 03:14
1
KUDOS
guerrero25 wrote:
If A=BC, is A>B ?

(1) 0<C<1
(2) A>0

[Reveal] Spoiler:
Isn't B alone sufficient to answer the question ?

Appreciate if some one could explain ..

Starting with the easy statement:
Statement 2 says that A>0, but no information has been given about B. So it is insufficient.
Statement 1 says that C is a gractional value, lying between 0 and 1. No info about A and B. Clearly Insufficient.
The answer has to be either C or E.
On combining the statements we get:
A>0 and 0<C<1. Do notice that A and B can be fractional values also.
Now consider,
A=0.1 and C=0.9, since A=BC therefore B=1/9. Here B>A.
Now consider,
A=0.9 and C=0.1, since A=BC, therefore B=9. Here also B>A.
If one takes integer values of A, then also B>A.
Hence sufficient.
+1C
_________________

Kudos [?]: 1679 [1], given: 62

Director
Status: Done with formalities.. and back..
Joined: 15 Sep 2012
Posts: 636

Kudos [?]: 653 [1], given: 23

Location: India
Concentration: Strategy, General Management
Schools: Olin - Wash U - Class of 2015
WE: Information Technology (Computer Software)
Re: If A=BC, is A>B ? [#permalink]

Show Tags

28 Jan 2013, 03:32
1
KUDOS
guerrero25 wrote:
If A=BC, is A>B ?

(1) 0<C<1
(2) A>0

[Reveal] Spoiler:
Isn't B alone sufficient to answer the question ?

Appreciate if some one could explain ..

No, B is not sufficient. it just tells A>0 , But you dont know anything about B/C individually.

Each statement alone is insufficient, clearly as none has more than one variable when we need relation between 2.

On combining, we get A>0 and 0<C<1. Since A, C>0 thus B>0

Notice, multiplication by a fraction will alsways result in a lower number for any postive number.
Therefore if A =BC where 0<C<1
then A <B
Sufficient.
_________________

Lets Kudos!!!
Black Friday Debrief

Kudos [?]: 653 [1], given: 23

Director
Joined: 03 Aug 2012
Posts: 899

Kudos [?]: 887 [0], given: 322

Concentration: General Management, General Management
GMAT 1: 630 Q47 V29
GMAT 2: 680 Q50 V32
GPA: 3.7
WE: Information Technology (Investment Banking)
Re: If A=BC, is A>B ? [#permalink]

Show Tags

29 Jan 2013, 22:43
My Say

(1). C belongs to (0,1)

=> C is +ve => A and B should have same signs

Case 1: A,B are -ve => A=-3 and B=-4 => A>B
Case 2: A,B are +ve => A=3 and B=4 => A<B

=>Insufficient

(2). A>0

Case 1: B is -ve => A=3 , B=-1 => A>B
Case 2 : B is +ve => A=3 , B=4 => A <B
=>Insufficient

Combined
A>0 => Case 2 only of Statement 1 Hence (C).
_________________

Rgds,
TGC!
_____________________________________________________________________
I Assisted You => KUDOS Please
_____________________________________________________________________________

Kudos [?]: 887 [0], given: 322

Verbal Forum Moderator
Joined: 10 Oct 2012
Posts: 627

Kudos [?]: 1358 [0], given: 136

Re: If A=BC, is A>B ? [#permalink]

Show Tags

30 Jan 2013, 06:52
A=BC;
1. 0<C<1 = 0<(A/B)<1

or 0<AB<B^2 = B(A-B)<0.

Now either B>0;A-B<0 or the other way around. Hence, not sufficient.

2.A>0. Not sufficient.

Taken together, C>0,A>0 hence B has to be positive. Thus, A-B<0.

C.
_________________

Kudos [?]: 1358 [0], given: 136

Re: If A=BC, is A>B ?   [#permalink] 30 Jan 2013, 06:52
Display posts from previous: Sort by

If A=BC, is A>B ?

 Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.