• NEW! FREE Beat The GMAT Quizzes
    NEW! FREE Beat The GMAT Quizzes
    NEW! FREE Beat The GMAT Quizzes
    Hundreds of Questions Highly Detailed Reporting Expert Explanations TAKE A FREE GMAT QUIZ
  • 7 CATs FREE!
    If you earn 100 Forum Points

    Engage in the Beat The GMAT forums to earn
    100 points for $49 worth of Veritas practice GMATs FREE

    Veritas Prep
    VERITAS PRACTICE GMAT EXAMS
    Earn 10 Points Per Post
    Earn 10 Points Per Thanks
    Earn 10 Points Per Upvote
    REDEEM NOW

DS OG 12 # 152

This topic has 1 expert reply and 3 member replies

DS OG 12 # 152

Post
If Carmen had 12 more tapes she would have twice as many tapes as Rafael. Does Carmen have fewer tapes then Rafael?

S1. Rafael has more then 5 tapes
S2. Carmen has fewer than 12 tapes



I got this right however i think it was by accident. Any one care to share their approach with me and so we can compare?

  • +1 Upvote Post
  • Quote
  • Flag

GMAT/MBA Expert

GMAT Instructor
Joined
21 Jan 2009
Posted:
3650 messages
Followed by:
82 members
Upvotes:
267
GMAT Score:
760
Facebook Logo
Post
HPengineer wrote:
If Carmen had 12 more tapes she would have twice as many tapes as Rafael. Does Carmen have fewer tapes then Rafael?

S1. Rafael has more then 5 tapes
S2. Carmen has fewer than 12 tapes



I got this right however i think it was by accident. Any one care to share their approach with me and so we can compare?
Take C + 12 = 2 R from stem. C will always be EVEN as C and R are whole numbers. Then try answering if C < R.

S1. If R > 5, then C + 12 is at least 12 as C and R are whole numbers. When R is 6, C is 0, making C < R as true, but when R is 12, C = R. So insufficient

S2. If C < 12, then it can at most be 10 to ensure C and R are whole numbers. When C is 10, R is 11, making C < R as true, which remains as true for all smaller possibilities for C. So sufficient

B

_________________
The mind is everything. What you think you become. –Lord Buddha



Sanjeev K Saxena
Quantitative Instructor
The Princeton Review - Manya Abroad
Lucknow-226001

www.manyagroup.com

  • +1 Upvote Post
  • Quote
  • Flag
Free GMAT Practice Test How can you improve your test score if you don't know your baseline score? Take a free online practice exam. Get started on achieving your dream score today! Sign up now.
Legendary Member Default Avatar
Joined
26 Apr 2010
Posted:
759 messages
Followed by:
3 members
Upvotes:
85
Post
also got B
the number of tapes Carmen-c
the number of tapes Rafael-r
we are given
c+12=2r
r=c/2+6
and asked if r>c, or
(c/2+6)-c>0
c+12-2c>0
is c<12
(1) insuffiicent, here to answer definitely we need to prove that r<12, but given that r>5
(2) c<12 suffiicent

  • +1 Upvote Post
  • Quote
  • Flag
Master | Next Rank: 500 Posts Default Avatar
Joined
24 Mar 2010
Posted:
165 messages
Followed by:
1 members
Upvotes:
2
Post
Ok heres how i solved it... Im wondering if its dangerous to solve similar probems with out inequalities...

S1. Rafael has more then 5 tapes

C + 12 = 2R so plug 6 in for R and solve for C which = 0 so less tapes then Rafael

Now try a larger number say 20 for R and you will get C = 38 which is more tapes then Rafaeal therefore S1 is Insuff.



S2. Carmen has fewer than 12 tapes

Here i simply plugged in 11 for C and solved for R

11+12= 2R or 23/2 = R so R = 11.5 which is greater then C so statement is sufficient.

What troubled me here is that i did not get a integer for R... How can you have half a tape? Shouldnt this be a hidden constraint problem since were dealing with items?

  • +1 Upvote Post
  • Quote
  • Flag
Senior | Next Rank: 100 Posts
Joined
13 Oct 2009
Posted:
55 messages
Upvotes:
3
Facebook Logo
Post
@HPengineer:

i solved it in the same way...... Very Happy

  • +1 Upvote Post
  • Quote
  • Flag
  • Veritas Prep
    Free Veritas GMAT Class
    Experience Lesson 1 Live Free

    Available with Beat the GMAT members only code

    MORE DETAILS
    Veritas Prep
  • e-gmat Exclusive Offer
    Get 300+ Practice Questions
    25 Video lessons and 6 Webinars for FREE

    Available with Beat the GMAT members only code

    MORE DETAILS
    e-gmat Exclusive Offer
  • Economist Test Prep
    Free Trial & Practice Exam
    BEAT THE GMAT EXCLUSIVE

    Available with Beat the GMAT members only code

    MORE DETAILS
    Economist Test Prep
  • The Princeton Review
    FREE GMAT Exam
    Know how you'd score today for $0

    Available with Beat the GMAT members only code

    MORE DETAILS
    The Princeton Review
  • Target Test Prep
    5-Day Free Trial
    5-day free, full-access trial TTP Quant

    Available with Beat the GMAT members only code

    MORE DETAILS
    Target Test Prep
  • Magoosh
    Magoosh
    Study with Magoosh GMAT prep

    Available with Beat the GMAT members only code

    MORE DETAILS
    Magoosh
  • EMPOWERgmat Slider
    1 Hour Free
    BEAT THE GMAT EXCLUSIVE

    Available with Beat the GMAT members only code

    MORE DETAILS
    EMPOWERgmat Slider
  • PrepScholar GMAT
    5 Day FREE Trial
    Study Smarter, Not Harder

    Available with Beat the GMAT members only code

    MORE DETAILS
    PrepScholar GMAT
  • Kaplan Test Prep
    Free Practice Test & Review
    How would you score if you took the GMAT

    Available with Beat the GMAT members only code

    MORE DETAILS
    Kaplan Test Prep
  • Varsity Tutors
    Award-winning private GMAT tutoring
    Register now and save up to $200

    Available with Beat the GMAT members only code

    MORE DETAILS
    Varsity Tutors

Top First Responders*

1 Brent@GMATPrepNow 40 first replies
2 Ian Stewart 40 first replies
3 Scott@TargetTestPrep 39 first replies
4 Jay@ManhattanReview 28 first replies
5 GMATGuruNY 25 first replies
* Only counts replies to topics started in last 30 days
See More Top Beat The GMAT Members

Most Active Experts

1 image description Scott@TargetTestPrep

Target Test Prep

159 posts
2 image description Max@Math Revolution

Math Revolution

90 posts
3 image description Brent@GMATPrepNow

GMAT Prep Now Teacher

58 posts
4 image description Ian Stewart

GMATiX Teacher

49 posts
5 image description GMATGuruNY

The Princeton Review Teacher

38 posts
See More Top Beat The GMAT Experts