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

 It is currently 25 Sep 2016, 02:16

### 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

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# If a > 0, is t^a > w^a ?

Author Message
TAGS:

### Hide Tags

Manager
Joined: 31 Jul 2014
Posts: 152
GMAT 1: 630 Q48 V29
Followers: 0

Kudos [?]: 42 [0], given: 373

If a > 0, is t^a > w^a ? [#permalink]

### Show Tags

06 Sep 2015, 21:23
00:00

Difficulty:

95% (hard)

Question Stats:

32% (03:37) correct 68% (01:15) wrong based on 50 sessions

### HideShow timer Statistics

If a > 0, is $$t^a$$ > $$w^a$$?

(1) t > w
(2) t = 2w
[Reveal] Spoiler: OA

Last edited by Engr2012 on 07 Sep 2015, 08:06, edited 1 time in total.
Formatted the question
Manager
Status: Perspiring
Joined: 15 Feb 2012
Posts: 119
Concentration: Marketing, Strategy
GPA: 3.6
WE: Engineering (Computer Software)
Followers: 6

Kudos [?]: 94 [0], given: 216

Re: If a > 0, is t^a > w^a ? [#permalink]

### Show Tags

07 Sep 2015, 00:32
This is a typical GMAT type question that you can expect...

For such questions remember to consider:
1. Values <-1
2. -1 < Values < 0
3. 0 < Values < 1
4. 1 < Values
[color=#0000ff]And you will never get such questions wrong !!
[/color]

Option1: The values differ when T,W are +VE and when they are -VE

Option 2: This is a TRAP.
All those who will substitute value of 't' and and cancel out the terms on LHS & RHS - WILL GET THIS WRONG.
You can cancel the terms ONLY if they are positive.

Combinig 1 & 2,
We are left with only +ve values. For which the given equation is always consistent.
Hence C.
Jamboree GMAT Instructor
Status: GMAT Expert
Affiliations: Jamboree Education Pvt Ltd
Joined: 15 Jul 2015
Posts: 294
Location: India
Followers: 62

Kudos [?]: 218 [1] , given: 1

Re: If a > 0, is t^a > w^a ? [#permalink]

### Show Tags

07 Sep 2015, 02:48
1
KUDOS
Expert's post
1
This post was
BOOKMARKED
Following property tested:

If x>0, a>b>0, then a^x>b^x

In this question : a = x, t= a, w=b

S1 - No idea about the sigh of t & w - Insufficient

S2 - Again no idea about the sigh of t & w - Insufficient

Combining - (and using another concept - NEVER cancel the variables on both sides of equality/ inequality) the statements - we know t>w and w>0 so, C is the answer.
_________________

Aryama Dutta Saikia
Jamboree Education Pvt. Ltd.

Manager
Joined: 10 Aug 2015
Posts: 98
Followers: 1

Kudos [?]: 58 [0], given: 20

Re: If a > 0, is t^a > w^a ? [#permalink]

### Show Tags

07 Sep 2015, 04:08
Solution:

Statement1 : t > w. We dont know if the numbers are positive or negative . Anyhow lets check both the cases.
If, t = 4 and w = 2. Since a>0, here $$t^{a} > w^{a}$$.
But, if t = -2, w = -4. Then t > w.Then for a=3, $$t^{a} > w^{a}$$ and for a=2, $$t^{a} < w^{a}$$.
Therefore, Insufficient.

Statement2 : t=2w. If t = -4, w = -2. Then t = 2w. Then for a=3, $$t^{a} < w^{a}$$ and for a=2, $$t^{a} > w^{a}$$.
Therefore, Insufficient.

Combined : We know that t and w can only be positive. Therefore, $$t^{a} > w^{a}$$ holds for all possible values.
Sufficient.

Option C
Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 1776
GPA: 3.82
Followers: 127

Kudos [?]: 1055 [1] , given: 0

If a > 0, is t^a > w^a ? [#permalink]

### Show Tags

07 Sep 2015, 07:22
1
KUDOS
Expert's post
Forget conventional ways of solving math questions. In DS, Variable approach is the easiest and quickest way to find the answer without actually solving the problem. Remember equal number of variables and equations ensures a solution.

If a > 0, is t^a > w^a ?

(1) t > w
(2) t = 2w

In the original condition there are 3 variables (a,t,w), and 1 equation (a>0) thus in order to match the number of variables and equations we need 2 equations more. Since there is 1 each i 1) and 2), C is likely the answer. In actual calculation, using both 1) & 2) we get t=2w>w--> w>0, t>0 thus the answer is yes and the conditions are sufficient. therefore the answer is C
_________________

MathRevolution: Finish GMAT Quant Section with 10 minutes to spare
The one-and-only World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy.
Find a 10% off coupon code for GMAT Club members.
Unlimited Access to over 120 free video lessons - try it yourself

If a > 0, is t^a > w^a ?   [#permalink] 07 Sep 2015, 07:22
Similar topics Replies Last post
Similar
Topics:
3 If a > 0 and b > 0, is a/b > b/a ? 6 21 Aug 2016, 04:13
3 If y > 0 is x > 0 ? 2 12 Sep 2015, 12:09
2 Is 5 > x > 0 ? 10 01 Mar 2011, 00:18
12 Is m+z > 0? 12 15 Jul 2008, 07:55
2 Is x > 0.05? 9 23 Jun 2007, 02:50
Display posts from previous: Sort by