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

    Available with Beat the GMAT members only code

    MORE DETAILS
    PrepScholar GMAT
  • 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
  • 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
  • Magoosh
    Magoosh
    Study with Magoosh GMAT prep

    Available with Beat the GMAT members only code

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

    Available with Beat the GMAT members only code

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

    Available with Beat the GMAT members only code

    MORE DETAILS
    EMPOWERgmat Slider
  • 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
  • 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
  • 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

Admissions Success Stories Are all of the terms in Set A equal?

This topic has 2 expert replies and 0 member replies

Are all of the terms in Set A equal?

Post Sat Aug 11, 2018 10:33 pm

Timer

00:00

Your Answer

A

B

C

D

E

Global Stats

Difficult



Are all of the terms in Set A equal?

(1) The sum of all 14 terms in Set A is 98.
(2) The sum of any 3 terms in Set A is 21.

OA C

Source: Veritas Prep

  • +1 Upvote Post
  • Quote
  • Flag

GMAT/MBA Expert

Post Sat Aug 11, 2018 10:51 pm
I posted a solution to a very similar problem here:

https://www.beatthegmat.com/from-og-12-t73239.html

_________________
Mitch Hunt
Private Tutor for the GMAT and GRE
GMATGuruNY@gmail.com

If you find one of my posts helpful, please take a moment to click on the "UPVOTE" icon.

Available for tutoring in NYC and long-distance.
For more information, please email me at GMATGuruNY@gmail.com.
Student Review #1
Student Review #2
Student Review #3

  • +1 Upvote Post
  • Quote
  • Flag
Free GMAT Practice Test How can you improve your test score if you don't know your baseline score? Take a free online practice exam. Get started on achieving your dream score today! Sign up now.

GMAT/MBA Expert

Post Sun Aug 12, 2018 5:14 am
BTGmoderatorDC wrote:
Are all of the terms in Set A equal?

(1) The sum of all 14 terms in Set A is 98.
(2) The sum of any 3 terms in Set A is 21.
Target question: Are all of the terms in Set A equal?

Statement 1: The sum of all 14 terms in Set A is 98
There are several possible scenarios that satisfy this statement. Here are two.
Case a: Set A = {7,7,7,7,7,7,7,7,7,7,7,7,7,7} in which case all of the numbers ARE equal
Case b: Set A = {0,0,0,0,0,0,0,0,0,0,0,0,0,98}, in which case all of the numbers are NOT equal
Since we cannot answer the target question with certainty, statement 1 is NOT SUFFICIENT

Statement 2: The sum of any 3 terms in Set A is 21
Under most conditions this statement WOULD be sufficient.
However, if set A has only 3 terms in total, then the statement is NOT sufficient.
To see what I mean, consider these two possible scenarios that satisfy statement 2:
Case a: Set A = {7,7,7} in which case all of the numbers ARE equal
Case b: Set A = {0, 0, 21}, in which case all of the numbers are NOT equal
Since we cannot answer the target question with certainty, statement 2 is NOT SUFFICIENT

Statements 1 and 2 combined
The combined statements ARE sufficient. Here's why:
Let's let a,b,c and d be four of the 14 numbers in set A.
From statement 2, we know that a + b + c = 21
Notice that if I replace ANY of these three values (a,b or c) with d, the sum must still be 21 (according to statement 2)
This tells us that a, b and c must all equal d.
I can use a similar approach to show that all of the other numbers must also equal d.
This means that all of the numbers in set A must be equal.
Since we can answer the target question with certainty, the COMBINED statements are SUFFICIENT

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 Jay@ManhattanReview 76 first replies
2 GMATGuruNY 61 first replies
3 Brent@GMATPrepNow 46 first replies
4 Rich.C@EMPOWERgma... 33 first replies
5 ceilidh.erickson 18 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 Brent@GMATPrepNow

GMAT Prep Now Teacher

107 posts
2 image description GMATGuruNY

The Princeton Review Teacher

94 posts
3 image description Jeff@TargetTestPrep

Target Test Prep

93 posts
4 image description Max@Math Revolution

Math Revolution

91 posts
5 image description Jay@ManhattanReview

Manhattan Review

88 posts
See More Top Beat The GMAT Experts