During a 10-week summer vacation, was the average : GMAT Data Sufficiency (DS)
Check GMAT Club Decision Tracker for the Latest School Decision Releases http://gmatclub.com/AppTrack

 It is currently 22 Jan 2017, 05:20

### 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

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

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# During a 10-week summer vacation, was the average

Author Message
TAGS:

### Hide Tags

Senior Manager
Joined: 12 Mar 2009
Posts: 311
Followers: 3

Kudos [?]: 322 [1] , given: 1

During a 10-week summer vacation, was the average [#permalink]

### Show Tags

22 Jan 2010, 23:27
1
KUDOS
5
This post was
BOOKMARKED
00:00

Difficulty:

55% (hard)

Question Stats:

65% (02:38) correct 35% (01:29) wrong based on 210 sessions

### HideShow timer Statistics

During a 10-week summer vacation, was the average (arithmetic mean) number of books that Carolyn read per week greater than the average number of books that Jacob read per week?

(1) Twice the average number of books that Carolyn read per week was greater than 5 less than twice the average number of books that Jacob read per week.

(2) During the last 5 weeks of the vacation, Carolyn read a total of 3 books more than Jacob.
[Reveal] Spoiler: OA

Last edited by Bunuel on 22 Oct 2013, 03:42, edited 2 times in total.
OA edited.
Math Expert
Joined: 02 Sep 2009
Posts: 36596
Followers: 7093

Kudos [?]: 93426 [2] , given: 10563

### Show Tags

23 Jan 2010, 00:27
2
KUDOS
Expert's post
4
This post was
BOOKMARKED
vaivish1723 wrote:
During a 10-week summer vacation, was the average (arithmetic mean) number of books that Carolyn read per week greater than the average number of books that Jacob
(1) Twice the average number of books that Carolyn read per week was greater
than 5 less than twice the average number of books that Jacob read per week.
(2) During the last 5 weeks of the vacation, Carolyn read a total of 3 books more
than Jacob.

Oa is
[Reveal] Spoiler:
a
.

Let $$c$$ be the average # of books that Carolyn read per week;
Let $$j$$ be the average # of books that Jacob read per week;

Question is c>j?

(1) $$2c>2j-5$$, if $$c=10<j=11$$ --> $$2*10=20>2*11-5=17$$ BUT if $$c=10>j=5$$ --> $$2*10=20>2*5-5=5$$, two different answers. Not sufficient.

(2) Clearly insufficient. In the second half of the 10 week period, Carolyn read 3 books more than Jacob. So her average for the second half will be greater than Jacob's, but we know nothing about the first half.

(1)+(2) Combined two statements also not sufficient to determine whether c>j.

_________________
Senior Manager
Joined: 06 Aug 2011
Posts: 405
Followers: 2

Kudos [?]: 192 [0], given: 82

Re: During a 10-week summer vacation, was the average [#permalink]

### Show Tags

30 Oct 2012, 03:56
Bunuel..it is necessary to try with num..

i have done lyk this..take C as the average of carolyn and J as the avg of jacob..

2c>2j-5
2j-2c<5

(J-C)<5/2..

so we dont knw its positive or negative..if its positive that means J avg is more than carolyn and vice versa..

Statement 2 is insufficient..

both are still insufficient to give the ans ..

So e..
_________________

Bole So Nehal.. Sat Siri Akal.. Waheguru ji help me to get 700+ score !

Math Expert
Joined: 02 Sep 2009
Posts: 36596
Followers: 7093

Kudos [?]: 93426 [0], given: 10563

Re: During a 10-week summer vacation, was the average [#permalink]

### Show Tags

30 Oct 2012, 04:47
sanjoo wrote:
Bunuel..it is necessary to try with num..

i have done lyk this..take C as the average of carolyn and J as the avg of jacob..

2c>2j-5
2j-2c<5

(J-C)<5/2..

so we dont knw its positive or negative..if its positive that means J avg is more than carolyn and vice versa..

Statement 2 is insufficient..

both are still insufficient to give the ans ..

So e..

Yes, you can do this way as well.
_________________
Current Student
Joined: 13 May 2011
Posts: 199
Concentration: Strategy, Technology
GMAT 1: 750 Q49 V42
GPA: 3.2
WE: Accounting (Consulting)
Followers: 14

Kudos [?]: 117 [0], given: 93

### Show Tags

22 Oct 2013, 03:36
Bunuel wrote:
vaivish1723 wrote:
During a 10-week summer vacation, was the average (arithmetic mean) number of books that Carolyn read per week greater than the average number of books that Jacob
(1) Twice the average number of books that Carolyn read per week was greater
than 5 less than twice the average number of books that Jacob read per week.
(2) During the last 5 weeks of the vacation, Carolyn read a total of 3 books more
than Jacob.

Oa is
[Reveal] Spoiler:
a
.

Let $$c$$ be the average # of books that Carolyn read per week;
Let $$j$$ be the average # of books that Jacob read per week;

Question is c>j?

(1) $$2c>2j-5$$, if $$c=10<j=11$$ --> $$2*10=20>2*11-5=17$$ BUT if $$c=10>j=5$$ --> $$2*10=20>2*5-5=5$$, two different answers. Not sufficient.

(2) Clearly insufficient. In the second half of the 10 week period, Carolyn read 3 books more than Jacob. So her average for the second half will be greater than Jacob's, but we know nothing about the first half.

(1)+(2) Combined two statements also not sufficient to determine whether c>j.

Bunuel, answer is seen in "edit" in the first post, kind of destroys the purpose of 'spoiler', could you please edit it out?
_________________

Stay positive! ^.^

My blog - http://www.mbafortech.com

GMAT Club Legend
Joined: 09 Sep 2013
Posts: 13497
Followers: 577

Kudos [?]: 163 [0], given: 0

Re: During a 10-week summer vacation, was the average [#permalink]

### Show Tags

01 Mar 2015, 20:02
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.
_________________
SVP
Joined: 17 Jul 2014
Posts: 2209
Location: United States (IL)
Concentration: Finance, Economics
Schools: Stanford '19 (S)
GMAT 1: 560 Q42 V26
GMAT 2: 550 Q39 V27
GMAT 3: 560 Q43 V24
GMAT 4: 650 Q49 V30
GPA: 3.92
WE: General Management (Transportation)
Followers: 20

Kudos [?]: 271 [0], given: 140

Re: During a 10-week summer vacation, was the average [#permalink]

### Show Tags

07 Apr 2016, 17:37
vaivish1723 wrote:
During a 10-week summer vacation, was the average (arithmetic mean) number of books that Carolyn read per week greater than the average number of books that Jacob read per week?

(1) Twice the average number of books that Carolyn read per week was greater than 5 less than twice the average number of books that Jacob read per week.

(2) During the last 5 weeks of the vacation, Carolyn read a total of 3 books more than Jacob.

my approach to prove that A, B, and C are not sufficient.

1. suppose average for C is 4, and so is for J.
2x4=8
2x4 - 5 = 3
so A for C > than A for J.

but it can be that A read 5/week and J read 4/week
10>3 true again, but values differ.

A and D are out

2. clearly insufficient.
B is out.

1+2
40 total books
C in first 5 weeks read 40/2 -3 = 17 books, and 23 in last 5 weeks
J on the contrary read 20 books in the first 5 weeks, and 20 in the last 5 weeks.
satisfies both 1 and 2, but averages are equal

now.
suppose C=5books/week = 50 books total
J = 4books/week = 40 total
C during first 5 weeks read 46 books, and 4 in the last 5 weeks
J read 39 in the first 5 weeks, and 1 in the last 5 weeks.
again, satisfies both conditions from 1 and 2..
2 outcomes - C is out
Re: During a 10-week summer vacation, was the average   [#permalink] 07 Apr 2016, 17:37
Similar topics Replies Last post
Similar
Topics:
While on a summer vacation in Hawaii, Carla goes for an ocea 4 10 Jul 2012, 19:16
Last year the 5 employees of company x took an average of 16 vacations 5 17 Mar 2011, 18:03
8 During a 10-week summer vacation, was the average 16 05 Jun 2008, 11:40
13 During a 40-mile trip, Marla traveled at an average speed of 5 19 May 2008, 17:25
1 During a 10-week summer vacation, was the average 6 26 Oct 2007, 22:31
Display posts from previous: Sort by
{"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0}