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

    Available with Beat the GMAT members only code

    MORE DETAILS
    Economist Test Prep
  • 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
  • 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
  • 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
  • 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
  • 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
  • The Princeton Review
    FREE GMAT Exam
    Know how you'd score today for $0

    Available with Beat the GMAT members only code

    MORE DETAILS
    The Princeton Review
  • 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

If it is true that z < 8 and 2z > -4, which of the fol

This topic has 3 expert replies and 0 member replies

If it is true that z < 8 and 2z > -4, which of the fol

Post Sun Mar 04, 2018 12:07 pm
If it is true that z < 8 and 2z > -4, which of the following must be true?

A. -8 < z < 4
B. z > 2
C. z > -8
D. z < 4
E. None of the above

The OA is C.

Can I say, z < 8 and 2z < -4 = z < -2, then -2 < z < 8, right?

Only C is always true, as ANY z from the TRUE range, -2 < z < 8, will be greater than -8.

Experts, any suggestion about this PS question? Thanks in advance.

  • +1 Upvote Post
  • Quote
  • Flag

GMAT/MBA Expert

mbawisdom Senior | Next Rank: 100 Posts Default Avatar
Joined
16 Dec 2014
Posted:
94 messages
Followed by:
4 members
Upvotes:
2
GMAT Score:
770
Post Sun Mar 04, 2018 2:04 pm
LUANDATO wrote:
If it is true that z < 8 and 2z > -4, which of the following must be true?

A. -8 < z < 4
B. z > 2
C. z > -8
D. z < 4
E. None of the above

The OA is C.

Can I say, z < 8 and 2z < -4 = z < -2, then -2 < z < 8, right?

Only C is always true, as ANY z from the TRUE range, -2 < z < 8, will be greater than -8.

Experts, any suggestion about this PS question? Thanks in advance.
I would have set it up the same way you did. You are correct in saying that -2 < Z < 8. Further you are correct in saying that C is true. Every possible value of Z is greater than -8.

A) doesn't hold --> test z = 5
B) doesn't hold --> test z = 1
D) doesn't hold --> test z = 5

  • +1 Upvote Post
  • Quote
  • Flag

GMAT/MBA Expert

Post Sun Mar 04, 2018 2:26 pm
LUANDATO wrote:
If it is true that z < 8 and 2z > -4, which of the following must be true?

A. -8 < z < 4
B. z > 2
C. z > -8
D. z < 4
E. None of the above

The OA is C.

Can I say, z < 8 and 2z < -4 = z < -2, then -2 < z < 8, right?

Only C is always true, as ANY z from the TRUE range, -2 < z < 8, will be greater than -8.

Experts, any suggestion about this PS question? Thanks in advance.
Hi LUANDATO,

Your conclusion, -2 < z < 8, is perfect.
So, if z is BETWEEN -2 and 8, then z must be greater than -8

Answer: C

Cheers,
Brent

_________________
Brent Hanneson – Creator of GMATPrepNow.com
Use our video course along with Beat The GMAT's free 60-Day Study Guide

Check out the online reviews of our course
Come see all of our free resources

  • +1 Upvote Post
  • Quote
  • Flag
GMAT Prep Now's comprehensive video course can be used in conjunction with Beat The GMAT’s FREE 60-Day Study Guide and reach your target score in 2 months!

GMAT/MBA Expert

Post Sun Mar 04, 2018 2:26 pm
LUANDATO wrote:
If it is true that z < 8 and 2z > -4, which of the following must be true?

A. -8 < z < 4
B. z > 2
C. z > -8
D. z < 4
E. None of the above

The OA is C.

Can I say, z < 8 and 2z < -4 = z < -2, then -2 < z < 8, right?

Only C is always true, as ANY z from the TRUE range, -2 < z < 8, will be greater than -8.

Experts, any suggestion about this PS question? Thanks in advance.
Hi LUANDATO,

Your conclusion, -2 < z < 8, is perfect.
So, if z is BETWEEN -2 and 8, then z must be greater than -8

Answer: C

Cheers,
Brent

_________________
Brent Hanneson – Creator of GMATPrepNow.com
Use our video course along with Beat The GMAT's free 60-Day Study Guide

Check out the online reviews of our course
Come see all of our free resources

  • +1 Upvote Post
  • Quote
  • Flag
GMAT Prep Now's comprehensive video course can be used in conjunction with Beat The GMAT’s FREE 60-Day Study Guide and reach your target score in 2 months!

Top First Responders*

1 GMATGuruNY 109 first replies
2 Brent@GMATPrepNow 44 first replies
3 Rich.C@EMPOWERgma... 37 first replies
4 Jay@ManhattanReview 25 first replies
5 Scott@TargetTestPrep 11 first replies
* Only counts replies to topics started in last 30 days
See More Top Beat The GMAT Members

Most Active Experts

1 image description GMATGuruNY

The Princeton Review Teacher

159 posts
2 image description Brent@GMATPrepNow

GMAT Prep Now Teacher

134 posts
3 image description Scott@TargetTestPrep

Target Test Prep

103 posts
4 image description Jeff@TargetTestPrep

Target Test Prep

94 posts
5 image description Rich.C@EMPOWERgma...

EMPOWERgmat

88 posts
See More Top Beat The GMAT Experts