• PrepScholar GMAT
    5 Day FREE Trial
    Study Smarter, Not Harder

    Available with Beat the GMAT members only code

    MORE DETAILS
    PrepScholar GMAT
  • EMPOWERgmat Slider
    1 Hour Free
    BEAT THE GMAT EXCLUSIVE

    Available with Beat the GMAT members only code

    MORE DETAILS
    EMPOWERgmat Slider
  • Kaplan Test Prep
    Free Practice Test & Review
    How would you score if you took the GMAT

    Available with Beat the GMAT members only code

    MORE DETAILS
    Kaplan Test Prep
  • Veritas Prep
    Free Veritas GMAT Class
    Experience Lesson 1 Live Free

    Available with Beat the GMAT members only code

    MORE DETAILS
    Veritas Prep
  • Magoosh
    Magoosh
    Study with Magoosh GMAT prep

    Available with Beat the GMAT members only code

    MORE DETAILS
    Magoosh
  • Economist Test Prep
    Free Trial & Practice Exam
    BEAT THE GMAT EXCLUSIVE

    Available with Beat the GMAT members only code

    MORE DETAILS
    Economist Test Prep
  • Target Test Prep
    5-Day Free Trial
    5-day free, full-access trial TTP Quant

    Available with Beat the GMAT members only code

    MORE DETAILS
    Target Test Prep
  • Varsity Tutors
    Award-winning private GMAT tutoring
    Register now and save up to $200

    Available with Beat the GMAT members only code

    MORE DETAILS
    Varsity Tutors
  • e-gmat Exclusive Offer
    Get 300+ Practice Questions
    25 Video lessons and 6 Webinars for FREE

    Available with Beat the GMAT members only code

    MORE DETAILS
    e-gmat Exclusive Offer

Is w + h^4 positive?

This topic has 4 expert replies and 0 member replies
jjjinapinch Senior | Next Rank: 100 Posts Default Avatar
Joined
24 Jul 2017
Posted:
83 messages

Is w + h^4 positive?

Post Thu Jul 27, 2017 12:12 pm
Is w + h^4 positive?

(1) h is positive
(2) w is positive

Official Guide question
Answer: B

  • +1 Upvote Post
  • Quote
  • Flag
Need free GMAT or MBA advice from an expert? Register for Beat The GMAT now and post your question in these forums!

GMAT/MBA Expert

Top Reply
Post Fri Dec 08, 2017 7:05 am
jjjinapinch wrote:
Is w + h^4 positive?

(1) h is positive
(2) w is positive
We need to determine whether w+h^4 is positive. First, we know that h^4 is always non-negative.

Let’s look at the 2 possibilities for the value of w+h^4:

1) If w is positive, then (w + h^4) will be positive.

2) If w is negative, then h^4 must be greater than |w| in order for (w + h^4) to be positive. For example if w = -4, then h^4 must be greater than 4 in order for (w + h^4) to be positive.

Statement One Alone:

h is positive

Since we already know that h^4 is positive and do not have any information about w, we do not have enough information to answer the question. We can eliminate answer choices A and D.

Statement Two Alone:

w is positive

Since we know that h^4 is non-negative, also knowing that w is positive is enough information to determine that w + h^4 is positive. Statement two is sufficient to answer the question.

Answer: B

_________________

Scott Woodbury Stewart Founder & CEO
GMAT Quant Self-Study Course - 500+ lessons 3000+ practice problems 800+ HD solutions
5-Day Free Trial 5-DAY FREE, FULL-ACCESS TRIAL TTP QUANT

  • +1 Upvote Post
  • Quote
  • Flag
Top Reply
Post Thu Jul 27, 2017 10:40 pm
jjjinapinch wrote:
Is w + h^4 positive?

(1) h is positive
(2) w is positive

Official Guide question
Answer: B
We need to ensure whether (w + h^4) positive.

Since the exponent of h is 4, an even number, whether h is positive or negative, h^4 is positive.

Thus, (w + h^4) is positive, if

1. w is positive, or
2. w is negative, but |w| < h^4

(w + h^4) is NOT positive, if

w is negative, and |w| ≥ h^4

Statement 1: h is positive.

We already know the nature of h^4, we are not interested in the nature of h. Insufficient.

Statement 2: w is positive.

We already deduced that if w is positive, (w + h^4) is positive. Sufficient.

The correct answer: B

Hope this helps!

Download free ebook: Manhattan Review GMAT Quantitative Question Bank Guide

-Jay
_________________
Manhattan Review GMAT Prep

Locations: New York | Singapore | Doha | Lausanne | and many more...

Schedule your free consultation with an experienced GMAT Prep Advisor! Click here.

  • +1 Upvote Post
  • Quote
  • Flag

GMAT/MBA Expert

Post Fri Dec 08, 2017 7:05 am
jjjinapinch wrote:
Is w + h^4 positive?

(1) h is positive
(2) w is positive
We need to determine whether w+h^4 is positive. First, we know that h^4 is always non-negative.

Let’s look at the 2 possibilities for the value of w+h^4:

1) If w is positive, then (w + h^4) will be positive.

2) If w is negative, then h^4 must be greater than |w| in order for (w + h^4) to be positive. For example if w = -4, then h^4 must be greater than 4 in order for (w + h^4) to be positive.

Statement One Alone:

h is positive

Since we already know that h^4 is positive and do not have any information about w, we do not have enough information to answer the question. We can eliminate answer choices A and D.

Statement Two Alone:

w is positive

Since we know that h^4 is non-negative, also knowing that w is positive is enough information to determine that w + h^4 is positive. Statement two is sufficient to answer the question.

Answer: B

_________________

Scott Woodbury Stewart Founder & CEO
GMAT Quant Self-Study Course - 500+ lessons 3000+ practice problems 800+ HD solutions
5-Day Free Trial 5-DAY FREE, FULL-ACCESS TRIAL TTP QUANT

  • +1 Upvote Post
  • Quote
  • Flag
Post Thu Jul 27, 2017 10:40 pm
jjjinapinch wrote:
Is w + h^4 positive?

(1) h is positive
(2) w is positive

Official Guide question
Answer: B
We need to ensure whether (w + h^4) positive.

Since the exponent of h is 4, an even number, whether h is positive or negative, h^4 is positive.

Thus, (w + h^4) is positive, if

1. w is positive, or
2. w is negative, but |w| < h^4

(w + h^4) is NOT positive, if

w is negative, and |w| ≥ h^4

Statement 1: h is positive.

We already know the nature of h^4, we are not interested in the nature of h. Insufficient.

Statement 2: w is positive.

We already deduced that if w is positive, (w + h^4) is positive. Sufficient.

The correct answer: B

Hope this helps!

Download free ebook: Manhattan Review GMAT Quantitative Question Bank Guide

-Jay
_________________
Manhattan Review GMAT Prep

Locations: New York | Singapore | Doha | Lausanne | and many more...

Schedule your free consultation with an experienced GMAT Prep Advisor! Click here.

  • +1 Upvote Post
  • Quote
  • Flag

Best Conversation Starters

1 lheiannie07 116 topics
2 LUANDATO 68 topics
3 swerve 65 topics
4 ardz24 65 topics
5 Roland2rule 64 topics
See More Top Beat The GMAT Members...

Most Active Experts

1 image description Scott@TargetTestPrep

Target Test Prep

198 posts
2 image description Brent@GMATPrepNow

GMAT Prep Now Teacher

181 posts
3 image description Jeff@TargetTestPrep

Target Test Prep

168 posts
4 image description Rich.C@EMPOWERgma...

EMPOWERgmat

134 posts
5 image description GMATGuruNY

The Princeton Review Teacher

119 posts
See More Top Beat The GMAT Experts