• 7 CATs FREE!
    If you earn 100 Forum Points

    Engage in the Beat The GMAT forums to earn
    100 points for $49 worth of Veritas practice GMATs FREE

    Veritas Prep
    VERITAS PRACTICE GMAT EXAMS
    Earn 10 Points Per Post
    Earn 10 Points Per Thanks
    Earn 10 Points Per Upvote
    REDEEM NOW

What is the average (arithmetic mean) of a list of

This topic has 1 expert reply and 0 member replies

What is the average (arithmetic mean) of a list of

Post
What is the average (arithmetic mean) of a list of 6 consecutive two-digit integers?

(1) The remainder when the fourth integer is divided by 5 is 3.
(2) The ratio of the largest integer to the smallest integer is 5:4.

The OA is the option B .

Experts, may you show me what is the best approach to solve this DS question? I am confused about the ratio.

  • +1 Upvote Post
  • Quote
  • Flag
Top Reply
Post
M7MBA wrote:
What is the average (arithmetic mean) of a list of 6 consecutive two-digit integers?

(1) The remainder when the fourth integer is divided by 5 is 3.
(2) The ratio of the largest integer to the smallest integer is 5:4.

The OA is the option B .

Experts, may you show me what is the best approach to solve this DS question? I am confused about the ratio.
We have to find out the average (arithmetic mean) of a list of 6 consecutive two-digit integers.

Let's take each statement one by one.

(1) The remainder when the fourth integer is divided by 5 is 3.

Case 1: Say the 6 consecutive two-digit integers are 20, 21, 22, 23, 24, and 25. The average = 22.5.
Case 2: Say the 6 consecutive two-digit integers are 30, 31, 32, 33, 34, and 35. The average = 32.5.

No unique answer. Insufficient.

(2) The ratio of the largest integer to the smallest integer is 5 : 4.

Say the largest integer = 5k and the smallest is 4k, thus 5k - 4k = k. The value of k must be 5 since there 6 consecutive integers.

Thus, the smallest integer = 4k = 5*4 = 20. Thus, the 6 consecutive two-digit integers are 20, 21, 22, 23, 24, and 25. And the average = 22.5. Sufficient.

The correct answer: B

Hope this helps!
_________________
Manhattan Review GMAT Prep

Locations: New York | Jakarta | Nanjing | Berlin | and many more...

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

  • +1 Upvote Post
  • Quote
  • Flag
  • 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
  • EMPOWERgmat Slider
    1 Hour Free
    BEAT THE GMAT EXCLUSIVE

    Available with Beat the GMAT members only code

    MORE DETAILS
    EMPOWERgmat Slider
  • PrepScholar GMAT
    5 Day FREE Trial
    Study Smarter, Not Harder

    Available with Beat the GMAT members only code

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

    Available with Beat the GMAT members only code

    MORE DETAILS
    Economist Test Prep
  • 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
  • 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
  • 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
  • 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
  • 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

Top First Responders*

1 Brent@GMATPrepNow 64 first replies
2 fskilnik@GMATH 58 first replies
3 Jay@ManhattanReview 46 first replies
4 GMATGuruNY 34 first replies
5 Rich.C@EMPOWERgma... 24 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 fskilnik@GMATH

GMATH Teacher

120 posts
2 image description Brent@GMATPrepNow

GMAT Prep Now Teacher

99 posts
3 image description Max@Math Revolution

Math Revolution

88 posts
4 image description Jay@ManhattanReview

Manhattan Review

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

EMPOWERgmat

65 posts
See More Top Beat The GMAT Experts