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

It is currently 16 Dec 2018, 12:19

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.

Close

Request Expert Reply

Confirm Cancel
Events & Promotions in December
PrevNext
SuMoTuWeThFrSa
2526272829301
2345678
9101112131415
16171819202122
23242526272829
303112345
Open Detailed Calendar
  • Free GMAT Prep Hour

     December 16, 2018

     December 16, 2018

     03:00 PM EST

     04:00 PM EST

    Strategies and techniques for approaching featured GMAT topics
  • FREE Quant Workshop by e-GMAT!

     December 16, 2018

     December 16, 2018

     07:00 AM PST

     09:00 AM PST

    Get personalized insights on how to achieve your Target Quant Score.

If S^2 > T^2 , which of the following must be true?

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 51229
If S^2 > T^2 , which of the following must be true?  [#permalink]

Show Tags

New post 19 Jul 2018, 00:43
00:00
A
B
C
D
E

Difficulty:

  15% (low)

Question Stats:

79% (00:47) correct 21% (00:51) wrong based on 61 sessions

HideShow timer Statistics

examPAL Representative
User avatar
G
Joined: 07 Dec 2017
Posts: 841
If S^2 > T^2 , which of the following must be true?  [#permalink]

Show Tags

New post Updated on: 19 Jul 2018, 03:05
1
Bunuel wrote:
If S^2 > T^2 , which of the following must be true?


(A) S > T

(B) S^2 > T

(C) ST > 0

(D) |S| > |T|

(E) ST < 0


As all we're given are equations, we'll work with them.
This is a Precise approach.

Simplifying our given data gives S^2 - T^2 > 0 --> (S - T)(S + T) > 0

So both S - T and S + T are positive in which case both S and T must be positive and S > T.
Or both S - T and S + T are negative in which case both S and T must be negative and S < T.

Looking at our answer choices, (A), (C), (E) are all directly contradicted by one of the above options.
(D) works because if both S and T are positive then S > T --> |S| > |T| and if both are negative then S < T means that S has a larger absolute value.
(B) can fail for some fractional values (such as T = 0.5 and S = 0.6 so S > T but S^2 < T)

(D) is our answer.
_________________

Image
Sign up for 7-day free trial
Image


Originally posted by DavidTutorexamPAL on 19 Jul 2018, 00:49.
Last edited by DavidTutorexamPAL on 19 Jul 2018, 03:05, edited 1 time in total.
SC Moderator
User avatar
P
Joined: 30 Jan 2015
Posts: 672
Location: India
Concentration: Operations, Marketing
GPA: 3.5
Re: If S^2 > T^2 , which of the following must be true?  [#permalink]

Show Tags

New post 19 Jul 2018, 01:41
Bunuel wrote:
If S^2 > T^2 , which of the following must be true?


(A) S > T --> Incorrect, fails if S is -ve and T is +ve
(B) S^2 > T --> Incorrect, fails in case of fractions
(C) ST > 0 --> Incorrect, fails in case of opposite sign
(D) |S| > |T| --> Correct, means exactly the same, absolute value of a number = squared value of the number
(E) ST < 0 --> Incorrect, fails in case both S and T have same sign

Hence, D.
_________________

The few, the fearless !

Thanks :-)

e-GMAT Representative
User avatar
D
Joined: 04 Jan 2015
Posts: 2323
Re: If S^2 > T^2 , which of the following must be true?  [#permalink]

Show Tags

New post 19 Jul 2018, 04:05

Solution



Given:
    • S^2 > T^2

To find:
• Among the given option, which one is correct.

Approach and Working:

    • \(S^2 > T^2\)
      o It only means that Absolute value of S is greater than T.
         For example: \(3^2>2^2\) and if you see|3|>|2| and |-3| >|-2|
      o Thus, |s|> |T|

Hence, the correct answer is option D.

Answer: D
_________________








Register for free sessions
Number Properties | Algebra |Quant Workshop

Success Stories
Guillermo's Success Story | Carrie's Success Story

Ace GMAT quant
Articles and Question to reach Q51 | Question of the week

Must Read Articles
Number Properties – Even Odd | LCM GCD | Statistics-1 | Statistics-2 | Remainders-1 | Remainders-2
Word Problems – Percentage 1 | Percentage 2 | Time and Work 1 | Time and Work 2 | Time, Speed and Distance 1 | Time, Speed and Distance 2
Advanced Topics- Permutation and Combination 1 | Permutation and Combination 2 | Permutation and Combination 3 | Probability
Geometry- Triangles 1 | Triangles 2 | Triangles 3 | Common Mistakes in Geometry
Algebra- Wavy line | Inequalities

Practice Questions
Number Properties 1 | Number Properties 2 | Algebra 1 | Geometry | Prime Numbers | Absolute value equations | Sets



| '4 out of Top 5' Instructors on gmatclub | 70 point improvement guarantee | www.e-gmat.com

Director
Director
User avatar
P
Joined: 31 Oct 2013
Posts: 883
Concentration: Accounting, Finance
GPA: 3.68
WE: Analyst (Accounting)
If S^2 > T^2 , which of the following must be true?  [#permalink]

Show Tags

New post 19 Jul 2018, 12:52
Bunuel wrote:
If S^2 > T^2 , which of the following must be true?


(A) S > T

(B) S^2 > T

(C) ST > 0

(D) |S| > |T|

(E) ST < 0



Note: Squared value and absolute value are alike.

The best answer is D.
Target Test Prep Representative
User avatar
P
Status: Founder & CEO
Affiliations: Target Test Prep
Joined: 14 Oct 2015
Posts: 4295
Location: United States (CA)
Re: If S^2 > T^2 , which of the following must be true?  [#permalink]

Show Tags

New post 22 Jul 2018, 17:30
Bunuel wrote:
If S^2 > T^2 , which of the following must be true?


(A) S > T

(B) S^2 > T

(C) ST > 0

(D) |S| > |T|

(E) ST < 0


Taking the square root of both sides, we have:

|S| > |T|

Note: If you are wondering why B is not true, take S = 2/5 and T = 1/5.

Answer: D
_________________

Scott Woodbury-Stewart
Founder and CEO

GMAT Quant Self-Study Course
500+ lessons 3000+ practice problems 800+ HD solutions

GMAT Club Bot
Re: If S^2 > T^2 , which of the following must be true? &nbs [#permalink] 22 Jul 2018, 17:30
Display posts from previous: Sort by

If S^2 > T^2 , which of the following must be true?

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


Copyright

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®.