BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem
TTP OnDemand GMAT Video Course
Featured Course

Target Test Prep GMAT OnDemand

Scott Woodbury-Stewart’s private virtual classroom — 400 hours of master-class video lessons for the GMAT Focus Edition.

  • 715+ score guarantee — highest in the industry (99th percentile)
  • 52 chapters · 1,500+ lessons · 4,000+ practice questions
  • 400 hours of video · 1,500+ instructor-led HD smartboard lessons
  • 300,000+ students accepted to Harvard, Stanford, Wharton, Booth & Sloan & more
  • 24/7 live support + weekly Zoom office hours with GMAT instructors
  • TTP AI Assist — 24/7 AI-powered virtual tutor for instant help
  • 1,200+ flashcards + AI-powered study assistant & daily calendar
  • OnDemand, LiveTeach & GMAT Bootcamp formats available
  • Also: GRE, SAT Math & Executive Assessment courses
  • MBA Admissions Consulting now available
  • 🏆 2025 EdTech Breakthrough Award: Test Prep Solution Provider of the Year
  • 200,000+ students served
  • 5-day free trial — $0 to start, no auto-billing, cancel anytime
★★★★★ 5.0 (559 reviews)
130-pt guarantee
$0 to start then $127/mo
Start Free 5-Day Trial Read 559 Reviews →

is a/b > c/d?

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
User avatar
GMAT Instructor
Posts: 3650
Joined: Wed Jan 21, 2009 4:27 amFollowed by: 80 members
Location: India
Thanked: 267 times
GMAT Score:760
by sanju09 » Fri Oct 07, 2011 4:36 am
If a, b, c, and d are positive integers, is a/b > c/d?

(1) a > c.

(2) b > d.
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
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Data Sufficiency |
Legendary Member
Posts: 966
Joined: Sat Jan 02, 2010 8:06 amFollowed by: 21 members
Thanked: 230 times

by shankar.ashwin » Fri Oct 07, 2011 4:49 am
E IMO
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
User avatar
GMAT Instructor
Posts: 3650
Joined: Wed Jan 21, 2009 4:27 amFollowed by: 80 members
Location: India
Thanked: 267 times
GMAT Score:760

by sanju09 » Fri Oct 07, 2011 5:00 am
shankar.ashwin wrote:E IMO
Correct! What's your reasoning, by the way?
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
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 3835
Joined: Fri Apr 02, 2010 10:00 pmFollowed by: 523 members
Location: Milpitas, CA
Thanked: 1854 times
GMAT Score:770

by Anurag@Gurome » Fri Oct 07, 2011 5:08 am
sanju09 wrote:If a, b, c, and d are positive integers, is a/b > c/d?

(1) a > c.

(2) b > d.
(1) a > c
If a = 5, b = 10, c = 2, d = 8, then a/b = 5/10 = 1/2 and c /d = 2/8 = 1/4; here a/b > c/d
If a = 5, b = 20, c = 2, d = 4, then a/b = 5/20 = 1/4 and c /d = 2/4 = 1/2; here a/b < c/d
We do not get a definite answer; NOT sufficient.

(2) b > d
We can take the same examples as in statement 1; again statement 2 is NOT sufficient.

Combining (1) and (2) also, if we take the same examples as in statement 1, again we do not get a definite answer; NOT sufficient.

The correct answer is E.
Anurag Mairal, Ph.D., MBA
GMAT Expert, Admissions and Career Guidance
Gurome, Inc.
1-800-566-4043 (USA)

Join Our Facebook Groups
GMAT with Gurome
https://www.facebook.com/groups/272466352793633/
Admissions with Gurome
https://www.facebook.com/groups/461459690536574/
Career Advising with Gurome
https://www.facebook.com/groups/360435787349781/
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Legendary Member
Posts: 966
Joined: Sat Jan 02, 2010 8:06 amFollowed by: 21 members
Thanked: 230 times

by shankar.ashwin » Fri Oct 07, 2011 5:12 am
Its definitely not A,B or D for we cannot compare numerators alone or denominators alone.

Together, we know a>c and b>d,

But we can have multiple possibilities for this,

2/10 > 1/8, you could also have 2/10<1/2.

Both satisfies the conditions. So E
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
User avatar
GMAT Instructor
Posts: 15539
Joined: Tue May 25, 2010 12:04 pmFollowed by: 1906 members
Location: New York, NY
Thanked: 13060 times
GMAT Score:790

by GMATGuruNY » Fri Oct 07, 2011 8:34 am
sanju09 wrote:If a, b, c, and d are positive integers, is a/b > c/d?

(1) a > c.

(2) b > d.
Since the question is restricted to positive integers, it can be rephrased:

Is ad > bc?

Maximize a and d, minimize b and c, while satisfying the two statements:
a=10, d=10, b=11, c=1.
ad > bc.

Minimize a and d, maximize b and c, while satisfying the two statements:
a=10, d=1, b=100, c=9.
ad < bc.

Since the combinations above satisfy both statements, and in the first case ad > bc and in the second case ad < bc, INSUFFICIENT.

The correct answer is E.
Private tutor exclusively for the GMAT and GRE, with over 20 years of experience.
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].
Student Review #1
Student Review #2
Student Review #3
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Master | Next Rank: 500 Posts
Posts: 197
Joined: Thu Sep 15, 2011 10:22 amFollowed by: 2 members
Thanked: 6 times

by parul9 » Fri Oct 07, 2011 8:01 pm
E! :)
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
User avatar
Senior | Next Rank: 100 Posts
Posts: 57
Joined: Tue Apr 19, 2011 7:39 pmFollowed by: 2 members
Location: Singapore
Thanked: 6 times

by abhi0697 » Sat Oct 08, 2011 6:38 pm
sanju09 wrote:If a, b, c, and d are positive integers, is a/b > c/d?

(1) a > c.

(2) b > d.


Kindly check out the below link for video solution:


https://www.youtube.com/watch?v=hEtUJyVs-KY

_____________________________________________________
I2-Infiniti Education
GMAT Classes in Singapore
www.i2-infiniti.com
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Legendary Member
Posts: 608
Joined: Sun Jun 19, 2011 11:16 amFollowed by: 8 members
Thanked: 37 times

by saketk » Mon Oct 10, 2011 3:55 am
Typically this type of questions can be solved by picking absolute values. Mitch has provided a wonderful explanation for this. IMO E
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 273
Joined: Tue Sep 21, 2010 5:37 amFollowed by: 74 members
Location: Durham, NC
Thanked: 154 times
GMAT Score:770

by Whitney Garner » Mon Oct 10, 2011 7:37 pm
sanju09 wrote:If a, b, c, and d are positive integers, is a/b > c/d?

(1) a > c.

(2) b > d.
We can use simple theory as well. Because everything is positive, we can cross multiply (which is nice because it is easier to compare products than fractions).

a/b > c/d ?

ad > bc?

Statement (1): a>c
So one piece on the left side is bigger than one piece on the right side, but we don't know about the relative sizes of d and b so we have no clue.

Statement (2): b>d
So one piece on the right side is bigger than one piece on the left side, but we don't know about the relative sizes of a and c so we have no clue.

Statements Together: a>c and b>d
The problem is that we have split up the big pieces. One is on the left side (the a) and one is on the right side (the b). So each side has 1 bigger piece and 1 smaller piece, so there is NO way to tell which one rules the other.

Think about how this is different from an example like:
If a, b, c, and d are positive integers, is a/b > c/d?

(1) a > c.

(2) d > b.
Now all the bigger stuff is on one side and all the smaller stuff is on the other. It is clear (together) that we have enough info!

:)
Whit
Whitney Garner
GMAT/GRE/EA Instructor & Anxiety/Accommodations Coach
www.whitneygarner.com

Contributor to Beat The GMAT!

Math is a lot like love - a simple idea that can easily get complicated :heart-eyes:
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
User avatar
Legendary Member
Posts: 516
Joined: Fri Jul 31, 2009 3:22 pmFollowed by: 13 members
Thanked: 112 times

by smackmartine » Mon Oct 10, 2011 8:07 pm
IMO E

(1) a > c. (we don't know anything about b,d) - Insufficient

(2) b > d. (we don't know anything about a,c) - Insufficient

Combining (1) and (2)

(a=1/2) > (c=1/3) and (b=2) >(d=1) -----------> 1/4 >1/3 (NO)

Also,
(a=3) > (c=2) and (b=1) >(d=1/2) -----------> 3 >1 (YES)

So, Insufficient.
Smack is Back ...
It takes time and effort to explain, so if my comment helped you please press Thanks button :)
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
User avatar
GMAT Instructor
Posts: 3650
Joined: Wed Jan 21, 2009 4:27 amFollowed by: 80 members
Location: India
Thanked: 267 times
GMAT Score:760

by sanju09 » Tue Oct 11, 2011 2:16 am
Whitney Garner wrote:
sanju09 wrote:If a, b, c, and d are positive integers, is a/b > c/d?

(1) a > c.

(2) b > d.
We can use simple theory as well. Because everything is positive, we can cross multiply (which is nice because it is easier to compare products than fractions).

a/b > c/d ?

ad > bc?

Statement (1): a>c
So one piece on the left side is bigger than one piece on the right side, but we don't know about the relative sizes of d and b so we have no clue.

Statement (2): b>d
So one piece on the right side is bigger than one piece on the left side, but we don't know about the relative sizes of a and c so we have no clue.

Statements Together: a>c and b>d
The problem is that we have split up the big pieces. One is on the left side (the a) and one is on the right side (the b). So each side has 1 bigger piece and 1 smaller piece, so there is NO way to tell which one rules the other.

Think about how this is different from an example like:
If a, b, c, and d are positive integers, is a/b > c/d?

(1) a > c.

(2) d > b.
Now all the bigger stuff is on one side and all the smaller stuff is on the other. It is clear (together) that we have enough info!

:)
Whit
Do you mean [spoiler]C[/spoiler] should be the answer, Whitney?

Oh! Now its alright on a second look.
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
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1