GMAT Question of the Day - Daily to your Mailbox; hard ones only

It is currently 15 Nov 2018, 15:13

Close

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
Your Progress

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

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Close

Request Expert Reply

Confirm Cancel
Events & Promotions in November
PrevNext
SuMoTuWeThFrSa
28293031123
45678910
11121314151617
18192021222324
2526272829301
Open Detailed Calendar
  • Free GMAT Strategy Webinar

     November 17, 2018

     November 17, 2018

     07:00 AM PST

     09:00 AM PST

    Nov. 17, 7 AM PST. Aiming to score 760+? Attend this FREE session to learn how to Define your GMAT Strategy, Create your Study Plan and Master the Core Skills to excel on the GMAT.
  • GMATbuster's Weekly GMAT Quant Quiz # 9

     November 17, 2018

     November 17, 2018

     09:00 AM PST

     11:00 AM PST

    Join the Quiz Saturday November 17th, 9 AM PST. The Quiz will last approximately 2 hours. Make sure you are on time or you will be at a disadvantage.

If M is the set of all consecutive multiples of 9 between 100 and 500,

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 50613
If M is the set of all consecutive multiples of 9 between 100 and 500,  [#permalink]

Show Tags

New post 17 Sep 2015, 00:27
15
00:00
A
B
C
D
E

Difficulty:

  55% (hard)

Question Stats:

69% (02:35) correct 31% (02:26) wrong based on 319 sessions

HideShow timer Statistics

If M is the set of all consecutive multiples of 9 between 100 and 500, what is the median of M?

A. 300
B. 301
C. 301.5
D. 302.5
E. 306

Kudos for a correct solution.

_________________

New to the Math Forum?
Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

Most Helpful Expert Reply
Math Expert
User avatar
V
Joined: 02 Aug 2009
Posts: 7034
Re: If M is the set of all consecutive multiples of 9 between 100 and 500,  [#permalink]

Show Tags

New post 17 Sep 2015, 03:25
8
5
Bunuel wrote:
If M is the set of all consecutive multiples of 9 between 100 and 500, what is the median of M?

A. 300
B. 301
C. 301.5
D. 302.5
E. 306

Kudos for a correct solution.



Without getting into too much of complication, we can see one simple issue in this q..
1) all numbers are in arith prog, so the median will be =average of (1st number + last number)..
first number is 108 and last number is 495...
answer = \(\frac{(108 + 495)}{2}=\frac{603}{2}\)
ans C 301.5
_________________

1) Absolute modulus : http://gmatclub.com/forum/absolute-modulus-a-better-understanding-210849.html#p1622372
2)Combination of similar and dissimilar things : http://gmatclub.com/forum/topic215915.html
3) effects of arithmetic operations : https://gmatclub.com/forum/effects-of-arithmetic-operations-on-fractions-269413.html


GMAT online Tutor

General Discussion
Math Revolution GMAT Instructor
User avatar
V
Joined: 16 Aug 2015
Posts: 6511
GMAT 1: 760 Q51 V42
GPA: 3.82
Premium Member
Re: If M is the set of all consecutive multiples of 9 between 100 and 500,  [#permalink]

Show Tags

New post 17 Sep 2015, 01:28
1
Forget conventional ways of solving math questions. In PS, IVY approach is the easiest and quickest way to find the answer.


If M is the set of all consecutive multiples of 9 between 100 and 500, what is the median of M?

A. 300
B. 301
C. 301.5
D. 302.5
E. 306

Since 100/9 =11.11, 500/9=55.55, M can be written as {9*12, 9*13, ...., 9*54, 9*55}. The number of elements of M is, therefore, 44(=55-12+1). Since the number of elements is even number the median is the average of the 22nd element(=9*33) and 23rd element(=9*34). So the median is (9*33 + 9*34)/2 = 301.5. 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.
"Only $99 for 3 month Online Course"
"Free Resources-30 day online access & Diagnostic Test"
"Unlimited Access to over 120 free video lessons - try it yourself"

Intern
Intern
avatar
Joined: 10 Nov 2014
Posts: 47
Re: If M is the set of all consecutive multiples of 9 between 100 and 500,  [#permalink]

Show Tags

New post 17 Sep 2015, 02:55
2
Bunuel wrote:
If M is the set of all consecutive multiples of 9 between 100 and 500, what is the median of M?

A. 300
B. 301
C. 301.5
D. 302.5
E. 306

Kudos for a correct solution.


M is a set of number multiples of 9 (100-500)
First, by this statement you will get the first number of this set 108 and the last number 495
Second, you will find that 108 is a 108/9 = 12th and 495/9 = 55th
Third, the question is asked about the median so (12th+55th)/2 = 33.5th
Hence, (33th+34th)/2 is the answer = [(9*33)+(9*34)]/2 = 301.5
Manager
Manager
avatar
Joined: 29 Jul 2015
Posts: 158
GMAT ToolKit User
Re: If M is the set of all consecutive multiples of 9 between 100 and 500,  [#permalink]

Show Tags

New post 17 Sep 2015, 15:10
1
Bunuel wrote:
If M is the set of all consecutive multiples of 9 between 100 and 500, what is the median of M?

A. 300
B. 301
C. 301.5
D. 302.5
E. 306

Kudos for a correct solution.


First multiple of 9 after 100 is 108 and multiple of 9 just before 500 is 495.
Now,
For evenly spaced sets, Mean = Median = (first term + last term)/ 2 = (108+495)/2 = 301.5

Answer:- C
CEO
CEO
User avatar
P
Status: GMATINSIGHT Tutor
Joined: 08 Jul 2010
Posts: 2698
Location: India
GMAT: INSIGHT
WE: Education (Education)
Reviews Badge
Re: If M is the set of all consecutive multiples of 9 between 100 and 500,  [#permalink]

Show Tags

New post 18 Sep 2015, 03:20
Bunuel wrote:
If M is the set of all consecutive multiples of 9 between 100 and 500, what is the median of M?

A. 300
B. 301
C. 301.5
D. 302.5
E. 306

Kudos for a correct solution.


First Multiple of 9 in the given range = 108
Last Multiple of 9 in the given range = 495

All consecutive multiples of 9 make and Arithmetic progressions

CONCEPT: In any Arithmetic Progression in which terms are equally spaced Mean = Median = Average of First and Last term of the series

i.e. Median = (108+495)/2 = 301.5

Answer: option C
_________________

Prosper!!!
GMATinsight
Bhoopendra Singh and Dr.Sushma Jha
e-mail: info@GMATinsight.com I Call us : +91-9999687183 / 9891333772
Online One-on-One Skype based classes and Classroom Coaching in South and West Delhi
http://www.GMATinsight.com/testimonials.html

ACCESS FREE GMAT TESTS HERE:22 ONLINE FREE (FULL LENGTH) GMAT CAT (PRACTICE TESTS) LINK COLLECTION

Current Student
avatar
B
Joined: 31 Oct 2011
Posts: 52
Location: India
GMAT 1: 660 Q48 V32
GPA: 3.56
WE: Programming (Computer Software)
Reviews Badge
Re: If M is the set of all consecutive multiples of 9 between 100 and 500,  [#permalink]

Show Tags

New post 19 Sep 2015, 18:25
1
Start with identifying first and last term.

First multiple of 9 after 100 is 108 = 9*12
Last multiple of 9 before 500 is 55 (since 500/9 = 55.x)

So, the sequence now has 9(12), 9(13), ... 9(55)

No. of terms = 55 - 12 + 1 = 44

=> Median is the mean of 22nd and 23rd terms
22nd term = 9*(22+11) = 9*33 = 297
23rd term = 297 + 9 = 306

(306 + 297)/2 = 301.5 (C)
Intern
Intern
User avatar
Joined: 14 Mar 2015
Posts: 33
Schools: ISB '18
Re: If M is the set of all consecutive multiples of 9 between 100 and 500,  [#permalink]

Show Tags

New post 19 Sep 2015, 21:05
4
Bunuel wrote:
If M is the set of all consecutive multiples of 9 between 100 and 500, what is the median of M?

A. 300
B. 301
C. 301.5
D. 302.5
E. 306

Kudos for a correct solution.


For consecutive intergers -
mean = median

So, first term is - next multiple of 9 > 100 = 108
last term is - multiple of 9 just prior to 500 = 495

So, mean = median = (First term + Last term)/2
=> (108 + 495)/2 = 301.5
_________________

It ain’t about how hard you hit. It’s about how hard you can get hit and keep moving forward;
how much you can take and keep moving forward.

That’s how winning is done!

Director
Director
User avatar
B
Status: I don't stop when I'm Tired,I stop when I'm done
Joined: 11 May 2014
Posts: 540
Location: Bangladesh
Concentration: Finance, Leadership
GPA: 2.81
WE: Business Development (Real Estate)
Re: If M is the set of all consecutive multiples of 9 between 100 and 500,  [#permalink]

Show Tags

New post 19 Sep 2015, 22:48
1
Bunuel wrote:
If M is the set of all consecutive multiples of 9 between 100 and 500, what is the median of M?

A. 300
B. 301
C. 301.5
D. 302.5
E. 306

Kudos for a correct solution.


We know,In any evenly spaced set the arithmetic mean is equal to the median and can be calculated by the formula,Mean=Median=\(\frac{First Term+Last Term}{2}\)

Now from the question we can find that,First Term of Consecutive multiples of 9 between 100 and 500=108 (9*12) and the Last Term of Consecutive multiples of 9 between 100 and 500 =495 (9*55)


Since it is an evenly spaced set,so the mean=mediam=\(\frac{108+495}{2}\) =301.5

So,the Correct Answer is C
_________________

Md. Abdur Rakib

Please Press +1 Kudos,If it helps
Sentence Correction-Collection of Ron Purewal's "elliptical construction/analogies" for SC Challenges

Intern
Intern
avatar
B
Joined: 29 Oct 2014
Posts: 38
Reviews Badge
Re: If M is the set of all consecutive multiples of 9 between 100 and 500,  [#permalink]

Show Tags

New post 20 Sep 2015, 00:22
GMATinsight wrote:
Bunuel wrote:
If M is the set of all consecutive multiples of 9 between 100 and 500, what is the median of M?

A. 300
B. 301
C. 301.5
D. 302.5
E. 306

Kudos for a correct solution.


First Multiple of 9 in the given range = 108
Last Multiple of 9 in the given range = 495

All consecutive multiples of 9 make and Arithmetic progressions

CONCEPT: In any Arithmetic Progression in which terms are equally spaced Mean = Median = Average of First and Last term of the series

i.e. Median = (108+495)/2 = 301.5

Answer: option C

GMATinsight can you please explain what do you mean by equally spaced. A small example would be very helpfull.
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 50613
Re: If M is the set of all consecutive multiples of 9 between 100 and 500,  [#permalink]

Show Tags

New post 20 Sep 2015, 20:41
Bunuel wrote:
If M is the set of all consecutive multiples of 9 between 100 and 500, what is the median of M?

A. 300
B. 301
C. 301.5
D. 302.5
E. 306

Kudos for a correct solution.


ECONOMIST GMAT TUTOR OFFICIAL SOLUTION:

The median of an arithmetic sequence is also its average. The average of an arithmetic sequence is the average of the smallest and largest terms. In set M, the smallest multiple of 9 is 108, and the largest is 495. Thus the average (and the median) is (108+495)/2 = 603/2 = 301.5.

Answer: C.
_________________

New to the Math Forum?
Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

Board of Directors
User avatar
P
Joined: 17 Jul 2014
Posts: 2645
Location: United States (IL)
Concentration: Finance, Economics
GMAT 1: 650 Q49 V30
GPA: 3.92
WE: General Management (Transportation)
GMAT ToolKit User Premium Member Reviews Badge
Re: If M is the set of all consecutive multiples of 9 between 100 and 500,  [#permalink]

Show Tags

New post 26 Oct 2015, 14:57
Did a little bit different...maybe it is more time consuming...
108 is 12*9
495 is 55*9

55-12+1 = 44, so we have to find mean of the 12+22 and 55-22 multiples of 9, or 34 and 33
(34+33)(9)/(2)= (69*9)/2, rewrite as 67*10-67 / 2 = 301.5
C.
Current Student
User avatar
D
Joined: 12 Aug 2015
Posts: 2633
Schools: Boston U '20 (M)
GRE 1: Q169 V154
GMAT ToolKit User Premium Member
Re: If M is the set of all consecutive multiples of 9 between 100 and 500,  [#permalink]

Show Tags

New post 16 Mar 2016, 01:22
Manager
Manager
avatar
Joined: 09 Jun 2015
Posts: 94
Re: If M is the set of all consecutive multiples of 9 between 100 and 500,  [#permalink]

Show Tags

New post 16 Mar 2016, 01:36
Bunuel wrote:
If M is the set of all consecutive multiples of 9 between 100 and 500, what is the median of M?

A. 300
B. 301
C. 301.5
D. 302.5
E. 306

Kudos for a correct solution.

There are 44 terms between 108 and 495
The median is 22.5.
Therefore, 99+22.5*9 = 301.5
Senior Manager
Senior Manager
User avatar
Joined: 31 Mar 2016
Posts: 386
Location: India
Concentration: Operations, Finance
GMAT 1: 670 Q48 V34
GPA: 3.8
WE: Operations (Commercial Banking)
GMAT ToolKit User Premium Member
Re: If M is the set of all consecutive multiples of 9 between 100 and 500,  [#permalink]

Show Tags

New post 10 Jun 2016, 12:50
multiples of 9 between 100 and 500 begin from 108 and ends at 495 that is from 9*12 to 9*55

so number of terms from 12 to 55 = 55-12+1 = 44 terms. With 21 to left and 21 to right the the average of 22nd and 23rd terms will be the Median.

22nd term = (12+22) - 1 [subtratcing 1 as this includes 12] = 33 * 9 = 297
23rd term will then be 34*9 = 306
.
(306+297)/2 = 301.5
Board of Directors
User avatar
P
Status: QA & VA Forum Moderator
Joined: 11 Jun 2011
Posts: 4210
Location: India
GPA: 3.5
WE: Business Development (Commercial Banking)
GMAT ToolKit User Premium Member
Re: If M is the set of all consecutive multiples of 9 between 100 and 500,  [#permalink]

Show Tags

New post 11 Jun 2016, 04:46
Bunuel wrote:
If M is the set of all consecutive multiples of 9 between 100 and 500, what is the median of M?

A. 300
B. 301
C. 301.5
D. 302.5
E. 306

Kudos for a correct solution.


M = { 108, 117..........486, 495}

M has 44 terms.........

Sum of the Series is 13266

Average ( Mean ) = 13266/44 =>301.5

Hence answer will be (C)

_________________

Thanks and Regards

Abhishek....

PLEASE FOLLOW THE RULES FOR POSTING IN QA AND VA FORUM AND USE SEARCH FUNCTION BEFORE POSTING NEW QUESTIONS

How to use Search Function in GMAT Club | Rules for Posting in QA forum | Writing Mathematical Formulas |Rules for Posting in VA forum | Request Expert's Reply ( VA Forum Only )

Non-Human User
User avatar
Joined: 09 Sep 2013
Posts: 8772
Premium Member
Re: If M is the set of all consecutive multiples of 9 between 100 and 500,  [#permalink]

Show Tags

New post 16 Jul 2018, 21:00
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________

GMAT Books | GMAT Club Tests | Best Prices on GMAT Courses | GMAT Mobile App | Math Resources | Verbal Resources

GMAT Club Bot
Re: If M is the set of all consecutive multiples of 9 between 100 and 500, &nbs [#permalink] 16 Jul 2018, 21:00
Display posts from previous: Sort by

If M is the set of all consecutive multiples of 9 between 100 and 500,

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  


Copyright

GMAT Club MBA Forum Home| About| Terms and Conditions and Privacy Policy| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne

Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.