Find all School-related info fast with the new School-Specific MBA Forum

It is currently 19 Sep 2014, 04:01

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.

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

Is x negative? (1) n*n*n(1-x*x) < 0 (2) x*x-1 < 0 The

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
Intern
Intern
avatar
Joined: 16 Apr 2003
Posts: 23
Location: Taiwan
Followers: 0

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

Is x negative? (1) n*n*n(1-x*x) < 0 (2) x*x-1 < 0 The [#permalink] New post 19 Sep 2003, 07:36
00:00
A
B
C
D
E

Difficulty:

(N/A)

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 0 sessions
1. Is x negative?

(1) n*n*n(1-x*x) < 0
(2) x*x-1 < 0

The answer is C.

2. What is the volume of a certain rectangular solid?

(1) Two adjacent faces of the solid have areas 15 and 24, respectively.
(2) Each of two opposite faces of the solid has area 40.

The answer is C.

Thanks:)[/code][/quote]
CEO
CEO
avatar
Joined: 15 Aug 2003
Posts: 3470
Followers: 60

Kudos [?]: 670 [0], given: 781

Re: Please help me with two DS [#permalink] New post 19 Sep 2003, 07:58
Joviest wrote:

(1) n*n*n(1-x*x) < 0

Here (1-x^2) can be greater than or less than 0

So cant say

(2) x*x-1 < 0

x^2 -1 < 0

x^2 < 1

Gives x >-1 or x<1 again cant say yes or no

Combine, we now know from 2 that 1-x^2 > 0

So that means x^2 <1 which means x>-1 and x<1


The answer is C.

2. What is the volume of a certain rectangular solid?

(1) Two adjacent faces of the solid have areas 15 and 24, respectively.
(2) Each of two opposite faces of the solid has area 40.

The answer is C.

Thanks:)[/code]
[/quote]

Its a bit confusing the way you have written the powers ...

(1) n*n*n(1-x*x) < 0

Here (1-x^2) can be greater than or less than 0

So cant say

(2) x*x-1 < 0

x^2 -1 < 0

x^2 < 1

Gives x >-1 or x<1 again cant say yes or no..insufficient

Combine, we now know from 2 that 1-x^2 > 0

but that still doesnt give the answer

I think E

2. What is the volume of a certain rectangular solid?

(1) Two adjacent faces of the solid have areas 15 and 24, respectively.

you can take any set lb,bh,lh ..it will get you the same answer

b*h = 15
l*h = 24

not sufficient three unknowns ,two equations.

(2) Each of two opposite faces of the solid has area 40.

l*b = 40

Not sufficient

Combine , three unknowns, three equations, sufficient...C
Intern
Intern
avatar
Joined: 19 Sep 2003
Posts: 1
Location: NYC
Followers: 0

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

 [#permalink] New post 19 Sep 2003, 13:47
I think the answer to the second question is C because...

If sides are adjacent, it means they share the length value of one side.
If sides are 15 and 24, the only common denominators are 3 and 1.

If the common leg is 3....
8 x 3 (24=area)
5 x 3 (15=area)
VOLUME = 8 x 3 x 5 = 120

if the common leg is 1...
24 x 1 (24=area)
15 x 1 (15=area)
VOLUME = 24 x 1 x 15= 360

A tells you it's either 120 or 360.

B tells you an area of a side is 40. That's impossible under the 2nd A scenario. The first A scenario fits right in.

you have side areas of
24 3x8
15 3x5
40 8x5

I'm not sure yet about #1
Intern
Intern
avatar
Joined: 13 Sep 2003
Posts: 43
Location: US
Followers: 0

Kudos [?]: 1 [0], given: 0

 [#permalink] New post 03 Nov 2003, 12:01
agree with praet on the first one..ans is E.
consider the value of x=-1/2 and x= 1/2.

in both cases x2 < 1.
  [#permalink] 03 Nov 2003, 12:01
    Similar topics Author Replies Last post
Similar
Topics:
Is x negative? 1) x^3(1-x^2)<0 2) x^2-1<0 yezz 4 15 Aug 2009, 23:43
1 Is x negative? 1) x^3(1-x^2)<0 2) x^2-1<0 I3igDmsu 4 21 Jun 2009, 17:59
Is x negative? 1) x^3(1-x^2)<0 2) x^2-1<0 yezz 3 10 Oct 2006, 12:31
if x<0, what is the value of ^1/4+(-x*|x|)^1/2 i guess MA 5 18 Jul 2006, 13:40
if x<0 what is the value of ^1/4+(-x*|x|)^1/2 joemama142000 8 14 Apr 2006, 16:24
Display posts from previous: Sort by

Is x negative? (1) n*n*n(1-x*x) < 0 (2) x*x-1 < 0 The

  Question banks Downloads My Bookmarks Reviews Important topics  


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

Powered by phpBB © phpBB Group and phpBB SEO

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®.