 It is currently 24 Mar 2019, 09:48 ### 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

#### Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here. # The greatest possible value of  Question banks Downloads My Bookmarks Reviews Important topics
Author Message
TAGS:
Moderator  Joined: 18 Apr 2015
Posts: 5888
Followers: 96

Kudos [?]: 1154 , given: 5471

The greatest possible value of [#permalink]
Expert's post 00:00

Question Stats: 77% (01:09) correct 22% (00:37) wrong based on 45 sessions
 Quantity A Quantity B The greatest possible value of $$\frac{2}{x-y}$$ where x and y are integers and $$9 \leq x \leq 12$$ and $$-2 \leq y \leq 8$$ 2

A. Quantity A is greater.
B. Quantity B is greater.
C. The two quantities are equal
D. The relationship cannot be determined from the information given.
[Reveal] Spoiler: OA

_________________

Last edited by chetan2u on 03 Nov 2018, 22:14, edited 1 time in total.
Corrected the question Manager Joined: 03 Dec 2017
Posts: 65
Followers: 0

Kudos [?]: 16  , given: 20

Re: The greatest possible value of [#permalink]
1
KUDOS
the answer is C?
that x could be 9, y could be 8
2/1=2 ?
Moderator  Joined: 18 Apr 2015
Posts: 5888
Followers: 96

Kudos [?]: 1154 , given: 5471

Re: The greatest possible value of [#permalink]
Expert's post

regards
_________________
Intern Joined: 11 Jan 2018
Posts: 44
Followers: 0

Kudos [?]: 33 , given: 7

Re: The greatest possible value of [#permalink]
Maximum value of Quantity A will be obtained if we put least possible value of x-y in denominator. That will be minimum value of x and maximum of y.
Hence, Choice C is correct.
_________________

Persistence >>>>>>> Success

Don't say thanks, just give KUDOS.
1 kudos = 1000 Thanks Manager Joined: 15 Feb 2018
Posts: 53
Followers: 1

Kudos [?]: 17  , given: 33

Re: The greatest possible value of [#permalink]
1
KUDOS
Yes, I have C as well. Because of the negative in x-y, plug in the least value of x (=9) with the greatest value of y (=8). Intern Joined: 23 Oct 2018
Posts: 1
Followers: 0

Kudos [?]: 1  , given: 0

Re: The greatest possible value of [#permalink]
1
KUDOS
I'm sorry to revive an old topic but I disagree with the answer.
What if X = 8.5 and Y = 8?
The difference would be 1/2 = 0.5, which would duplicate the value of A, making it bigger than B.
Is there something Im missing?
Supreme Moderator
Joined: 01 Nov 2017
Posts: 370
Followers: 5

Kudos [?]: 107 , given: 4

Re: The greatest possible value of [#permalink]
Expert's post
RCDMC wrote:
I'm sorry to revive an old topic but I disagree with the answer.
What if X = 8.5 and Y = 8?
The difference would be 1/2 = 0.5, which would duplicate the value of A, making it bigger than B.
Is there something Im missing?

Yes you are correct.
A could be actually infinity in the present state as it is NOT given that x and y are integers..
Carcass wrote:
 Quantity A Quantity B The greatest possible value of $$\frac{2}{x-y}$$ where $$9 \leq x \leq 12$$ and $$-2 \leq y \leq 8$$ 2

say x is 9 and y is 8.999999, $$\frac{2}{x-y}=\frac{2}{9-8.999999}=\frac{2}{0.000001}=2*10^6$$, way bigger than B

So editing to make it correct..
Now when we take them as integers we take minimum value of x as 9 and maximum value of y as 8
$$A=\frac{2}{x-y}=\frac{2}{9-8}=\frac{2}{1}=2=B$$
_________________

Some useful Theory.
1. Arithmetic and Geometric progressions : https://greprepclub.com/forum/progressions-arithmetic-geometric-and-harmonic-11574.html#p27048
2. Effect of Arithmetic Operations on fraction : https://greprepclub.com/forum/effects-of-arithmetic-operations-on-fractions-11573.html?sid=d570445335a783891cd4d48a17db9825
3. Remainders : https://greprepclub.com/forum/remainders-what-you-should-know-11524.html
4. Number properties : https://greprepclub.com/forum/number-property-all-you-require-11518.html
5. Absolute Modulus and Inequalities : https://greprepclub.com/forum/absolute-modulus-a-better-understanding-11281.html

Director Joined: 09 Nov 2018
Posts: 509
Followers: 0

Kudos [?]: 21 , given: 1

Re: The greatest possible value of [#permalink]
chetan2u wrote:
RCDMC wrote:
I'm sorry to revive an old topic but I disagree with the answer.
What if X = 8.5 and Y = 8?
The difference would be 1/2 = 0.5, which would duplicate the value of A, making it bigger than B.
Is there something Im missing?

Yes you are correct.
A could be actually infinity in the present state as it is NOT given that x and y are integers..
Carcass wrote:
 Quantity A Quantity B The greatest possible value of $$\frac{2}{x-y}$$ where $$9 \leq x \leq 12$$ and $$-2 \leq y \leq 8$$ 2

say x is 9 and y is 8.999999, $$\frac{2}{x-y}=\frac{2}{9-8.999999}=\frac{2}{0.000001}=2*10^6$$, way bigger than B

So editing to make it correct..
Now when we take them as integers we take minimum value of x as 9 and maximum value of y as 8
$$A=\frac{2}{x-y}=\frac{2}{9-8}=\frac{2}{1}=2=B$$

Please check that −2≤y≤8 means max value for y is 8 not even 8.000.......001, let alone 8.9999999, and
again for x, min vale is 9 because 9≤x≤12.

As a result, 2/(9-8)=2/1=2.
_______________________________________________________________
Please let me know if I am wrong.
Supreme Moderator
Joined: 01 Nov 2017
Posts: 370
Followers: 5

Kudos [?]: 107 , given: 4

Re: The greatest possible value of [#permalink]
Expert's post
AE wrote:
chetan2u wrote:
RCDMC wrote:
I'm sorry to revive an old topic but I disagree with the answer.
What if X = 8.5 and Y = 8?
The difference would be 1/2 = 0.5, which would duplicate the value of A, making it bigger than B.
Is there something Im missing?

Yes you are correct.
A could be actually infinity in the present state as it is NOT given that x and y are integers..
Carcass wrote:
 Quantity A Quantity B The greatest possible value of $$\frac{2}{x-y}$$ where $$9 \leq x \leq 12$$ and $$-2 \leq y \leq 8$$ 2

say x is 9 and y is 8.999999, $$\frac{2}{x-y}=\frac{2}{9-8.999999}=\frac{2}{0.000001}=2*10^6$$, way bigger than B

So editing to make it correct..
Now when we take them as integers we take minimum value of x as 9 and maximum value of y as 8
$$A=\frac{2}{x-y}=\frac{2}{9-8}=\frac{2}{1}=2=B$$

Please check that −2≤y≤8 means max value for y is 8 not even 8.000.......001, let alone 8.9999999, and
again for x, min vale is 9 because 9≤x≤12.

As a result, 2/(9-8)=2/1=2.
_______________________________________________________________
Please let me know if I am wrong.

Yes , that is correct,
For some reason I took −2≤y≤8 as −2≤y≤9..
If it is −2≤y≤8, we have to take minimum value of x-y to get maximum of 2/(x-y)... Ans least value of x-y is 1 when x is 9 and y is 8
_________________

Some useful Theory.
1. Arithmetic and Geometric progressions : https://greprepclub.com/forum/progressions-arithmetic-geometric-and-harmonic-11574.html#p27048
2. Effect of Arithmetic Operations on fraction : https://greprepclub.com/forum/effects-of-arithmetic-operations-on-fractions-11573.html?sid=d570445335a783891cd4d48a17db9825
3. Remainders : https://greprepclub.com/forum/remainders-what-you-should-know-11524.html
4. Number properties : https://greprepclub.com/forum/number-property-all-you-require-11518.html
5. Absolute Modulus and Inequalities : https://greprepclub.com/forum/absolute-modulus-a-better-understanding-11281.html

Intern Joined: 21 Dec 2018
Posts: 20
Followers: 0

Kudos [?]: 4 , given: 2

Re: The greatest possible value of [#permalink]
C
if we try all the border cases we can't seem to get x-y less than 1 in order to get A to its highest value with the lowest denominator Re: The greatest possible value of   [#permalink] 21 Dec 2018, 10:25
Display posts from previous: Sort by

# The greatest possible value of  Question banks Downloads My Bookmarks Reviews Important topics Powered by phpBB © phpBB Group Kindly note that the GRE® test is a registered trademark of the Educational Testing Service®, and this site has neither been reviewed nor endorsed by ETS®.