GMAT Question of the Day - Daily to your Mailbox; hard ones only
close

It is currently 22 Aug 2018, 01:00
Register
GMAT Club Tests
Decision Tracker
My Rewards
New posts
Unanswered

Close

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
Your Progress

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

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Go to My Error Log Learn more
Close

Request Expert Reply

Confirm Cancel

Is x+y < 1 (1) x < 8/9 (2) y < 1/8

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
  Sort by Date Sort by Kudos  
Search for:
 
Print view
First unread post
Author Message
TAGS:

Hide Tags
Intern
Intern
avatar
Joined: 06 Jan 2012
Posts: 26
Location: United States
Schools: Anderson FEMBA '15 (S)
Is x+y < 1 (1) x < 8/9 (2) y < 1/8  [#permalink]

Show Tags

New post 23 Mar 2012, 13:39
10
00:00
A
B
C
D
E

Difficulty:

  45% (medium)

Question Stats:

61% (00:37) correct 39% (00:32) wrong based on 413 sessions

HideShow timer Statistics

Is x+y < 1

(1) x < 8/9
(2) y < 1/8
Spoiler: OA

_________________

-If you like my post, consider giving KUDOS

Most Helpful Expert Reply
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 48119
Premium Member CAT Tests
Top Member of the Month
Re: Is x+y < 1  [#permalink]

Show Tags

New post 23 Mar 2012, 13:44
5
4
dddmba2012 wrote:
Is x+y < 1
1. x < 8/9
2. y < 1/8


Is x+y<1

(1) \(x<\frac{8}{9}=\frac{64}{72}\). Not sufficient by itself.

(2) \(y<\frac{1}{8}=\frac{9}{72}\). Not sufficient by itself.

(1)+(2) \(x+y<\frac{64}{72}+\frac{9}{72}=\frac{73}{72}\), so \(x+y<\frac{73}{72}\) --> \(x+y\) may or may not be less than 1 (\(x+y\) could be less than 1 as well as more than 1, in the range \((1,\frac{73}{72})\)). Not sufficient.

Answer: E.
_________________

New to the Math Forum?
Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

General Discussion
Intern
Intern
avatar
Joined: 12 Sep 2013
Posts: 2
Re: Is x+y < 1 (1) x < 8/9 (2) y < 1/8  [#permalink]

Show Tags

New post 24 Sep 2013, 07:05
Dear Bunuel,
Although i understand the solution after reading it,can you please help me in understanding the line of thinking.I never thought of multiplying the bases by a common factor.What concept's understanding would prompt me to ? :(

Thank you
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 48119
Premium Member CAT Tests
Top Member of the Month
Re: Is x+y < 1 (1) x < 8/9 (2) y < 1/8  [#permalink]

Show Tags

New post 24 Sep 2013, 07:32
fido wrote:
Dear Bunuel,
Although i understand the solution after reading it,can you please help me in understanding the line of thinking.I never thought of multiplying the bases by a common factor.What concept's understanding would prompt me to ? :(

Thank you


We need to compare some fractions. Easiest ways is to find the least common denominator and proceed.
_________________

New to the Math Forum?
Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

GMAT Tutor
avatar
S
Joined: 24 Jun 2008
Posts: 1345
Is x+y < 1 (1) x < 8/9 (2) y < 1/8  [#permalink]

Show Tags

New post 24 Sep 2013, 10:19
Is x+y < 1?
a) x < 8/9
b) y < 1/8

The answer to this question is E. By adding the inequalities, we find that x + y < 8/9 + 1/8 = 73/72, but it remains possible that x+y is somewhere between 1 and 73/72. It may be easier to see this using decimals, rather than fractions. Recall that 8/9 = 0.8888...., and that 1/8 = 0.125. Using both statements, we might have that x = 0.88, and that y = 0.121, so x+y can be equal to 1.01, and therefore can be greater than 1.
_________________

GMAT Tutor in Toronto

If you are looking for online GMAT math tutoring, or if you are interested in buying my advanced Quant books and problem sets, please contact me at ianstewartgmat at gmail.com

Manager
Manager
User avatar
S
Joined: 14 Jul 2016
Posts: 56
Location: India
Concentration: Strategy, Marketing
Schools: AGSM '20 (A)
GMAT 1: 650 Q48 V31
GPA: 3.5
WE: Analyst (Computer Software)
Reviews Badge
Re: Is x+y < 1 (1) x < 8/9 (2) y < 1/8  [#permalink]

Show Tags

New post 25 Jan 2017, 09:59
dddmba2012 wrote:
Is x+y < 1

(1) x < 8/9
(2) y < 1/8


Each statement alone doesn't convey anything.
If you combine the statements, then you get x+y < 73/72. x and y can have any value which is less than 8/9 and 1/8. Eg: x:8/9.001 y: 1/8.01
Hence E.
Intern
Intern
avatar
B
Joined: 17 Sep 2016
Posts: 44
GMAT 1: 640 Q44 V35
Re: Is x+y < 1 (1) x < 8/9 (2) y < 1/8  [#permalink]

Show Tags

New post 05 Mar 2017, 08:21
Again, failed to think 73/72 may be taken as 1 or more than 1 as well !!
Retired Moderator
User avatar
P
Joined: 19 Mar 2014
Posts: 969
Location: India
Concentration: Finance, Entrepreneurship
Schools: HBS '20, Stanford '20, Wharton '20, Kellogg '20, CBS '20, Haas '20
GPA: 3.5
GMAT ToolKit User Premium Member
Is x+y < 1 (1) x < 8/9 (2) y < 1/8  [#permalink]

Show Tags

New post 25 Jun 2017, 11:45
2
\(x+y < 1\)

(1) \(x < \frac{8}{9}\)

As we don't know the value of y, this equation is not sufficient =====> (1) NOT SUFFICIENT

(2) \(y < \frac{1}{8}\)

As we don't know the value of x, this equation is not sufficient =====> (2) NOT SUFFICIENT

Combining (1) & (2)

Lets solve x first

\(x < \frac{8}{9}\)

\(x < 8 * 0.11\)

\(x < 0.88\)

Lets solve for y

\(y < \frac{1}{8}\)

\(x < 0.125\)

Adding \(x + y = 0.88 + 0.125\)

We get \(x+y = 1.005\)

As the value of \(x + y\) can take the highest value as \(1.004\)ans any value lower than that which is \(< 1\)

We can say that x can be > 1 or x can be < 1

Hence, =====> Both (1) & (2) NOT SUFFICIENT

Hence, E is the Answer
_________________

"Nothing in this world can take the place of persistence. Talent will not: nothing is more common than unsuccessful men with talent. Genius will not; unrewarded genius is almost a proverb. Education will not: the world is full of educated derelicts. Persistence and determination alone are omnipotent."

Best AWA Template: https://gmatclub.com/forum/how-to-get-6-0-awa-my-guide-64327.html#p470475

EMPOWERgmat Instructor
User avatar
V
Status: GMAT Assassin/Co-Founder
Affiliations: EMPOWERgmat
Joined: 19 Dec 2014
Posts: 12226
Location: United States (CA)
GMAT 1: 800 Q51 V49
GRE 1: Q170 V170
Re: Is x+y < 1 (1) x < 8/9 (2) y < 1/8  [#permalink]

Show Tags

New post 20 Dec 2017, 17:19
Hi All,

When dealing with fractions in GMAT Quant questions, it's sometimes helpful to convert from fraction-to-decimal (doing so might make the requisite math faster or easier).

We're asked if (X+Y) is less than 1. This is a YES/NO question.

1) X < 8/9

This FACT tells us that X is LESS than .88888...., but we don't know anything about Y.
Fact 1 is INSUFFICIENT

2) Y < 1/8

This FACT tells us that Y is LESS than .125, but we don't know anything about X.
Fact 2 is INSUFFICIENT

Combined, we know that (X+Y) must be LESS than .8888.... + .125 = 1.01388888....

IF... the sum = 1, then the answer to the question is NO.
IF... the sum = 0, then the answer to the question is YES.

Combined, INSUFFICIENT

Final Answer:
Spoiler: ::
E


GMAT assassins aren't born, they're made,
Rich
_________________

760+: Learn What GMAT Assassins Do to Score at the Highest Levels
Contact Rich at: Rich.C@empowergmat.com

Rich Cohen

Co-Founder & GMAT Assassin

Special Offer: Save $75 + GMAT Club Tests Free
  Official GMAT Exam Packs + 70 Pt. Improvement Guarantee
www.empowergmat.com/

***********************Select EMPOWERgmat Courses now include ALL 6 Official GMAC CATs!***********************

Re: Is x+y < 1 (1) x < 8/9 (2) y < 1/8 &nbs [#permalink] 20 Dec 2017, 17:19
Print view
First unread post
Display posts from previous: Sort by

Is x+y < 1 (1) x < 8/9 (2) y < 1/8

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  

Moderators: chetan2u, VeritasKarishma, Bunuel, mikemcgarry, gmatbusters, amanvermagmat

Search for:

Events & Promotions

PREV
NEXT


GMAT Club MBA Forum Home| About| Terms and Conditions and Privacy Policy| GMAT Club Rules| Contact| Sitemap

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®.

Main navigation

GMAT Resources

Partners

MBA Resources

www.gmac.com|www.mba.com | | GMAT Club Rules | Terms and Conditions