Find all School-related info fast with the new School-Specific MBA Forum

It is currently 20 Dec 2014, 09:13

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.

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

A certain high school with a total enrollment of 900 student

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
Expert Post
2 KUDOS received
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 24607
Followers: 3805

Kudos [?]: 32866 [2] , given: 3580

A certain high school with a total enrollment of 900 student [#permalink] New post 03 Sep 2012, 05:10
2
This post received
KUDOS
Expert's post
6
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  45% (medium)

Question Stats:

65% (02:29) correct 35% (01:33) wrong based on 358 sessions
A certain high school with a total enrollment of 900 students held a science fair for three days last week. How many of the students enrolled in the high school attended the science fair on all three days?

(1) Of the students enrolled in the school, 30 percent attended the science fair on two or more days.
(2) Of the students enrolled in the school, 10 percent of those that attended the science fair on at least one day attended on all three days.

Practice Questions
Question: 34
Page: 277
Difficulty: 650
[Reveal] Spoiler: OA

_________________

NEW TO MATH FORUM? PLEASE READ THIS: ALL YOU NEED FOR QUANT!!!

PLEASE READ AND FOLLOW: 11 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory; 7. Remainders; 8. Overlapping Sets; 9. PDF of Math Book; 10. Remainders; 11. GMAT Prep Software Analysis NEW!!!; 12. SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) NEW!!!; 12. Tricky questions from previous years. NEW!!!;

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?
25 extra-hard Quant Tests

Expert Post
2 KUDOS received
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 24607
Followers: 3805

Kudos [?]: 32866 [2] , given: 3580

Re: A certain high school with a total enrollment of 900 student [#permalink] New post 03 Sep 2012, 05:11
2
This post received
KUDOS
Expert's post
3
This post was
BOOKMARKED
SOLUTION

A certain high school with a total enrollment of 900 students held a science fair for three days last week. How many of the students enrolled in the high school attended the science fair on all three days?

The trick here is that we don't know whether all of 900 students attended on at least one day. Meaning that there can be # of students which didn't take part in the fair.

So we have the following groups:
A. Attended on only one day
B. Attended on two days exactly
C. Attended on all three days
D. Not attended.
And the sum of these groups is A+B+C+D=900. We want to determine the value of C.

(1) Of the students enrolled in the school, 30 percent attended the science fair on two or more days. So, 900*0.3=270 attended 2 or more days --> B+C=270. Not sufficient.

(2) Of the students enrolled in the school, 10 percent of those that attended the science fair on at least one day attended on all three days --> 10%*(A+B+C)=C --> A+B=9C. Not sufficient.

(1)+(2) B+C=270, A+B=9C and A+B+C+D=900. Three equations four unknowns. Not sufficient.

Answer: E.
_________________

NEW TO MATH FORUM? PLEASE READ THIS: ALL YOU NEED FOR QUANT!!!

PLEASE READ AND FOLLOW: 11 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory; 7. Remainders; 8. Overlapping Sets; 9. PDF of Math Book; 10. Remainders; 11. GMAT Prep Software Analysis NEW!!!; 12. SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) NEW!!!; 12. Tricky questions from previous years. NEW!!!;

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?
25 extra-hard Quant Tests

1 KUDOS received
Intern
Intern
avatar
Joined: 28 Aug 2012
Posts: 48
Location: Austria
GMAT 1: 770 Q51 V42
Followers: 3

Kudos [?]: 32 [1] , given: 3

Re: A certain high school with a total enrollment of 900 student [#permalink] New post 03 Sep 2012, 05:37
1
This post received
KUDOS
Each statement alone is clearly not sufficient.

Statement (1) + (2) together:
900 * 0.3 = 270 students attended the fair on two or more days.
Since we don't know the number of students that didn't attend the fair at all or on one day, we don't know, how many students attended the fair on all three days.

It could be: 30 students on all three days, 240 students on two days, 30 students on one day, 600 students never.
It could be: 60 students on all three days, 210 students on two days, 330 students on one day, 300 students never.

Answer is E, both statements together not sufficient.
Expert Post
1 KUDOS received
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 24607
Followers: 3805

Kudos [?]: 32866 [1] , given: 3580

Re: A certain high school with a total enrollment of 900 student [#permalink] New post 07 Sep 2012, 05:06
1
This post received
KUDOS
Expert's post
SOLUTION

A certain high school with a total enrollment of 900 students held a science fair for three days last week. How many of the students enrolled in the high school attended the science fair on all three days?

The trick here is that we don't know whether all of 900 students attended on at least one day. Meaning that there can be # of students which didn't take part in the fair.

So we have the following groups:
A. Attended on only one day
B. Attended on two days exactly
C. Attended on all three days
D. Not attended.
And the sum of these groups is A+B+C+D=900. We want to determine the value of C.

(1) Of the students enrolled in the school, 30 percent attended the science fair on two or more days. So, 900*0.3=270 attended 2 or more days --> B+C=270. Not sufficient.

(2) Of the students enrolled in the school, 10 percent of those that attended the science fair on at least one day attended on all three days --> 10%*(A+B+C)=C --> A+B=9C. Not sufficient.

(1)+(2) B+C=270, A+B=9C and A+B+C+D=900. Three equations four unknowns. Not sufficient.

Answer: E.

Kudos points given to everyone with correct solution. Let me know if I missed someone.
_________________

NEW TO MATH FORUM? PLEASE READ THIS: ALL YOU NEED FOR QUANT!!!

PLEASE READ AND FOLLOW: 11 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory; 7. Remainders; 8. Overlapping Sets; 9. PDF of Math Book; 10. Remainders; 11. GMAT Prep Software Analysis NEW!!!; 12. SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) NEW!!!; 12. Tricky questions from previous years. NEW!!!;

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?
25 extra-hard Quant Tests

Expert Post
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 24607
Followers: 3805

Kudos [?]: 32866 [0], given: 3580

Re: A certain high school with a total enrollment of 900 student [#permalink] New post 01 Sep 2013, 10:35
Expert's post
Manager
Manager
avatar
Joined: 21 Oct 2013
Posts: 186
Location: Germany
Concentration: Accounting, International Business
GMAT 1: 660 Q45 V36
GPA: 3.91
Followers: 0

Kudos [?]: 17 [0], given: 19

Re: A certain high school with a total enrollment of 900 student [#permalink] New post 19 Dec 2013, 04:06
Bunuel wrote:
A certain high school with a total enrollment of 900 students held a science fair for three days last week. How many of the students enrolled in the high school attended the science fair on all three days?

(1) Of the students enrolled in the school, 30 percent attended the science fair on two or more days.
(2) Of the students enrolled in the school, 10 percent of those that attended the science fair on at least one day attended on all three days.

Practice Questions
Question: 34
Page: 277
Difficulty: 650




Stmt 1: 30 % attended on two or more days. so 270 students attended at least two days, but you get nothing about three days. IS

Stmt 2: 10 % of those that attended 1 day attended all three days. Since you don't know whether all 900 students attented once, this doesn't help. IS

Together: I still don't know nothing about the number of students in stmt 2 and stmt 1 doesn't help here. So still IS. Hence E.

Looks more complicated than it actually was. some logic thinking and the answer was there :)
Re: A certain high school with a total enrollment of 900 student   [#permalink] 19 Dec 2013, 04:06
    Similar topics Author Replies Last post
Similar
Topics:
2 Experts publish their posts in the topic A certain high school with a total enrollment of 900 gmat620 7 12 Nov 2009, 11:41
Of the students in a certain school, 15 percent are enrolled Ravshonbek 8 07 Dec 2007, 17:54
Of the students in a certain school, 15 percent are enrolled singh_amit19 1 09 Oct 2007, 14:31
The King School has an enrollment of 900 students. The Jamesk486 6 16 May 2007, 04:12
The King School has an enrollment of 900 students. The gamjatang 3 19 Nov 2005, 07:08
Display posts from previous: Sort by

A certain high school with a total enrollment of 900 student

  Question banks Downloads My Bookmarks Reviews Important topics  


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

Powered by phpBB © phpBB Group and phpBB SEO

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®.