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

It is currently 17 Nov 2018, 22:04

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 Quant Workshop by e-GMAT!

     November 18, 2018

     November 18, 2018

     07:00 AM PST

     09:00 AM PST

    Get personalized insights on how to achieve your Target Quant Score. November 18th, 7 AM PST
  • How to QUICKLY Solve GMAT Questions - GMAT Club Chat

     November 20, 2018

     November 20, 2018

     09:00 AM PST

     10:00 AM PST

    The reward for signing up with the registration form and attending the chat is: 6 free examPAL quizzes to practice your new skills after the chat.

Last year Department Store X had a sales total for December

  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: 50623
Last year Department Store X had a sales total for December  [#permalink]

Show Tags

New post 05 Mar 2014, 01:12
2
1
11
00:00
A
B
C
D
E

Difficulty:

  45% (medium)

Question Stats:

70% (01:35) correct 30% (01:52) wrong based on 745 sessions

HideShow timer Statistics

The Official Guide For GMAT® Quantitative Review, 2ND Edition

Last year Department Store X had a sales total for December that was 4 times the average (arithmetic mean) of the monthly sales totals for January through November. The sales total for December was what fraction of the sales total for the year?

(A) 1/4
(B) 4/15
(C) 1/3
(D) 4/11
(E) 4/5

Problem Solving
Question: 129
Category: Algebra; Arithmetic Applied problems; Statistics
Page: 78
Difficulty: 600


GMAT Club is introducing a new project: The Official Guide For GMAT® Quantitative Review, 2ND Edition - Quantitative Questions Project

Each week we'll be posting several questions from The Official Guide For GMAT® Quantitative Review, 2ND Edition and then after couple of days we'll provide Official Answer (OA) to them along with a slution.

We'll be glad if you participate in development of this project:
1. Please provide your solutions to the questions;
2. Please vote for the best solutions by pressing Kudos button;
3. Please vote for the questions themselves by pressing Kudos button;
4. Please share your views on difficulty level of the questions, so that we have most precise evaluation.

Thank you!

_________________

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

Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 50623
Re: Last year Department Store X had a sales total for December  [#permalink]

Show Tags

New post 05 Mar 2014, 01:12
2
2
SOLUTION

Last year Department Store X had a sales total for December that was 4 times the average (arithmetic mean) of the monthly sales totals for January through November. The sales total for December was what fraction of the sales total for the year?

(A) 1/4
(B) 4/15
(C) 1/3
(D) 4/11
(E) 4/5

Let x be the average sales per month for the first 11 months, then the total sales for the whole year would be (11 months) + (December) = 11x + 4x = 15x.

(December)/(Whole year) = 4x/(15x) = 4/15.

Answer: B.
_________________

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

Intern
Intern
avatar
Status: Trying to beat the gmat
Joined: 19 Nov 2012
Posts: 33
Location: Brazil
Concentration: General Management, Entrepreneurship
GMAT 1: 610 Q46 V28
Re: Last year Department Store X had a sales total for December  [#permalink]

Show Tags

New post 05 Mar 2014, 14:57
Lets consider each month sales as X, the december sales is 4 times the average of the other months, so december is 4X, to define what fraction of the total year sales must be fraction / total so will be 4x / 11x + 4x, 4x / 16x, and will be
1/4
Retired Moderator
User avatar
Joined: 20 Dec 2013
Posts: 175
Location: United States (NY)
GMAT 1: 640 Q44 V34
GMAT 2: 710 Q48 V40
GMAT 3: 720 Q49 V40
GPA: 3.16
WE: Consulting (Venture Capital)
GMAT ToolKit User Premium Member Reviews Badge
Re: Last year Department Store X had a sales total for December  [#permalink]

Show Tags

New post 05 Mar 2014, 16:20
1
Jan-Nov Avg Monthly Sales:Dec Sales
1:4

Dec Sales/(Jan-Nov Sales Total+Dec Sales)
4/[(11*1)+(1*4)]
4/15

B
_________________

MY GMAT BLOG - ADVICE - OPINIONS - ANALYSIS

Manager
Manager
User avatar
Status: GMATting
Joined: 21 Mar 2011
Posts: 105
Concentration: Strategy, Technology
GMAT 1: 590 Q45 V27
GMAT ToolKit User
Re: Last year Department Store X had a sales total for December  [#permalink]

Show Tags

New post 05 Mar 2014, 20:28
1
Let the monthy sales, on average, be x.
Monthly sales totals for January through November = 11x;
Sales Total for December = 4x;

We can write the equation: 4x/(11x + 4x) = 4x/15x = 4/15;

Ans is (B)
SVP
SVP
User avatar
Status: The Best Or Nothing
Joined: 27 Dec 2012
Posts: 1826
Location: India
Concentration: General Management, Technology
WE: Information Technology (Computer Software)
Re: Last year Department Store X had a sales total for December  [#permalink]

Show Tags

New post 06 Mar 2014, 02:08
2
Let sales from Jan to Nov = J + F +....... +N
Let sales in December = d

\(Avg = \frac{(J + F +....... +N)}{11}\)

\(d = 4 * \frac{(J + F +....... +N)}{11}\)

\((J + F +....... +N) = \frac{11d}{4}\) ...... Sales from Jan through Nov

Total sales Jan to Dec \(= \frac{11d}{4} + d = \frac{15d}{4}\)

The sales total for December is \(\frac{4}{15}\) fraction of the sales total for the year

Answer = B
_________________

Kindly press "+1 Kudos" to appreciate :)

Director
Director
User avatar
Joined: 25 Apr 2012
Posts: 689
Location: India
GPA: 3.21
WE: Business Development (Other)
Premium Member Reviews Badge
Re: Last year Department Store X had a sales total for December  [#permalink]

Show Tags

New post 06 Mar 2014, 03:02
1

Last year Department Store X had a sales total for December that was 4 times the average (arithmetic mean) of the monthly sales totals for January through November. The sales total for December was what fraction of the sales total for the year?

(A) 1/4
(B) 4/15
(C) 1/3
(D) 4/11
(E) 4/5



Sol: Let the average sale for Jan to Nov period is X then total sales in this period is 11X
Now sale in Dec 4X.
Total sale for Jan-Dec: 15X
Dec sale as fraction of Total sales 4X/15X or 4/15
Ans is B
_________________


“If you can't fly then run, if you can't run then walk, if you can't walk then crawl, but whatever you do you have to keep moving forward.”

Manager
Manager
avatar
Joined: 01 May 2013
Posts: 61
Re: Last year Department Store X had a sales total for December  [#permalink]

Show Tags

New post 06 Mar 2014, 14:34
1
Plugged in numbers. Set average to 1. Total for Jan-Nov is 11. Sales for Dec = 4. Yearly total 15. Dec = 4/15 of total.
Manager
Manager
avatar
Joined: 20 Dec 2013
Posts: 235
Location: India
Re: Last year Department Store X had a sales total for December  [#permalink]

Show Tags

New post 08 Mar 2014, 05:51
1
Let sum of sales from Jan to Nov=x
Sales in dec=y
To calculate:y/x+y
We're given
4x/11=y
x/y=11/4
Add 1 to both sides and reciprocate.
We get 4/15
Option B.

Posted from my mobile device
Director
Director
User avatar
G
Joined: 23 Jan 2013
Posts: 570
Schools: Cambridge'16
Re: Last year Department Store X had a sales total for December  [#permalink]

Show Tags

New post 01 Dec 2014, 20:19
By picking:

x/11=2, 22 in eleven months

2*4=8 in December, so

8/22+8=8/30=4/15

B
Intern
Intern
avatar
Status: I am working with SageNext Infotech LLC as a system Engineer. SageNext is a leading QuickBooks Hosting provider.
Joined: 01 Dec 2014
Posts: 1
Location: United States
Re: Last year Department Store X had a sales total for December  [#permalink]

Show Tags

New post 01 Dec 2014, 20:25
We absolutely love your post and find a lot of your post’s to be exactly I’m looking for. Does one offer guest writers to write content for you personally? I wouldn’t mind creating a post or elaborating on a lot of the subjects you write regarding here. Again, awesome weblog!
Director
Director
User avatar
B
Joined: 10 Mar 2013
Posts: 513
Location: Germany
Concentration: Finance, Entrepreneurship
GMAT 1: 580 Q46 V24
GPA: 3.88
WE: Information Technology (Consulting)
GMAT ToolKit User
Re: Last year Department Store X had a sales total for December  [#permalink]

Show Tags

New post 16 Nov 2015, 12:23
Bunuel wrote:
The Official Guide For GMAT® Quantitative Review, 2ND Edition

Last year Department Store X had a sales total for December that was 4 times the average (arithmetic mean) of the monthly sales totals for January through November. The sales total for December was what fraction of the sales total for the year?

(A) 1/4
(B) 4/15
(C) 1/3
(D) 4/11
(E) 4/5


We can use just some smart numbers here
December = 8; means that the average for each month Jan-Nov = 2 --> \(\frac{8}{8+11*2}=\frac{4}{15}\)Answer B
_________________

When you’re up, your friends know who you are. When you’re down, you know who your friends are.

Share some Kudos, if my posts help you. Thank you !

800Score ONLY QUANT CAT1 51, CAT2 50, CAT3 50
GMAT PREP 670
MGMAT CAT 630
KAPLAN CAT 660

Board of Directors
User avatar
P
Status: QA & VA Forum Moderator
Joined: 11 Jun 2011
Posts: 4222
Location: India
GPA: 3.5
WE: Business Development (Commercial Banking)
GMAT ToolKit User Premium Member
Re: Last year Department Store X had a sales total for December  [#permalink]

Show Tags

New post 25 Jul 2017, 08:45
Bunuel wrote:
Last year Department Store X had a sales total for December that was 4 times the average (arithmetic mean) of the monthly sales totals for January through November. The sales total for December was what fraction of the sales total for the year?

(A) 1/4
(B) 4/15
(C) 1/3
(D) 4/11
(E) 4/5


Total sales from January to November is \(11x\) (say)

Sales for December is \(4x\)

Total sales of the year is \(15x\)

So, the sales total for December was \(\frac{4}{15}\) part of the sales total for the year, answer will be (E)

_________________

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 )

Target Test Prep Representative
User avatar
P
Status: Founder & CEO
Affiliations: Target Test Prep
Joined: 14 Oct 2015
Posts: 4170
Location: United States (CA)
Re: Last year Department Store X had a sales total for December  [#permalink]

Show Tags

New post 26 Jul 2017, 15:30
Quote:
Last year Department Store X had a sales total for December that was 4 times the average (arithmetic mean) of the monthly sales totals for January through November. The sales total for December was what fraction of the sales total for the year?

(A) 1/4
(B) 4/15
(C) 1/3
(D) 4/11
(E) 4/5


We can let n = the average sales for months January through November, inclusive, and so the first eleven months’ sales = 11n and December’s sales = 4n.

The sum of sales for the entire year is 11n + 4n = 15n, so December was 4n/15n = 4/15 of the sales for the year.

Answer: B
_________________

Scott Woodbury-Stewart
Founder and CEO

GMAT Quant Self-Study Course
500+ lessons 3000+ practice problems 800+ HD solutions

Non-Human User
User avatar
Joined: 09 Sep 2013
Posts: 8803
Premium Member
Re: Last year Department Store X had a sales total for December  [#permalink]

Show Tags

New post 17 Sep 2018, 13:12
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: Last year Department Store X had a sales total for December &nbs [#permalink] 17 Sep 2018, 13:12
Display posts from previous: Sort by

Last year Department Store X had a sales total for December

  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®.