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.

It appears that you are browsing the GMAT Club forum unregistered!

Signing up is free, quick, and confidential.
Join other 500,000 members and get the full benefits of GMAT Club

Registration gives you:

Tests

Take 11 tests and quizzes from GMAT Club and leading GMAT prep companies such as Manhattan GMAT,
Knewton, and others. All are free for GMAT Club members.

Applicant Stats

View detailed applicant stats such as GPA, GMAT score, work experience, location, application
status, and more

Books/Downloads

Download thousands of study notes,
question collections, GMAT Club’s
Grammar and Math books.
All are free!

Thank you for using the timer!
We noticed you are actually not timing your practice. Click the START button first next time you use the timer.
There are many benefits to timing your practice, including:

What percentage of the current fourth graders at Liberation [#permalink]

Show Tags

27 Feb 2009, 10:58

5

This post was BOOKMARKED

00:00

A

B

C

D

E

Difficulty:

45% (medium)

Question Stats:

63% (02:10) correct
37% (01:08) wrong based on 268 sessions

HideShow timer Statistics

What percentage of the current fourth graders at Liberation Elementary School dressed in costume for Halloween for the past two years in a row (both this year and last year)?

(1) 60% of the current fourth graders at Liberation Elementary School dressed in costume for Halloween this year. (2) Of the current fourth graders at Liberation Elementary School who did not dress in costume for Halloween this year, 80% did not dress in costume last year.

Re: What percentage of the current fourth graders at Liberation [#permalink]

Show Tags

26 Nov 2014, 22:00

1

This post received KUDOS

Lets say there are 100 student statement 1 = 60 wore costume this year and 40 did not (insufficient) statement 2 = (alone says nothing about current year students) so insufficient Combining both, 60 wore costume this year and 40 did not last year 32 did not wore costuming and 68 did (assuming last year also there were 100 students) [here only we can conclude E is ans] so 68 wore costumes last year and 60 this year, but we don't know that these overlapping 60 are same students or not So IMO E is correct ans.

Statement 1: 60% of the current fourth graders at Liberation Elementary School dressed in costume for Halloween this year.

This alone does not give any details about the previous year so A and D are out.

Statement 2: Of the current fourth graders at Liberation Elementary School who did not dress in costume for Halloween this year, 80% did not dress in costume last year.

This statement alone does not give the % for this year so B is out.

Looking at them together we are still missing the info on the percentage of students who wore costume this year but did not wear it last year. so C is out.

It should be E. Even after combining both the statements, it does not clarify how many of 60% students that did not dress costume this year did dress last year.

Re: What percentage of the current fourth graders at Liberation [#permalink]

Show Tags

25 Feb 2013, 16:06

OA is E. This is the explanation from MGMAT.

We can divide the current fourth graders into 4 categories:

(1) The percentage that dressed in costume this year ONLY. (2) The percentage that dressed in costume last year ONLY. (3) The percentage that did NOT dress in costume either this year or last year. (4) The percentage that dressed in costume BOTH years.

We need to determine the last category (category 4) in order to answer the question.

(1) INSUFFICIENT: Let's assume there are 100 current fourth graders (this simply helps to make this percentage question more concrete). 60 of them dressed in costume this year, while 40 did not. However, we don't know how many of these 60 dressed in costume last year, so we can't divide this 60 up into categories 1 and 2.

(2) INSUFFICIENT: This provides little relevant information on its own because we don't know how many of the students didn't dress up in costumes this year and the statement references that value.

(1) AND (2) INSUFFICIENT: From statement 1 we know that 60 dressed up in costumes this year, but 40 did not. Statement 2 tells us that 80% of these 40, or 32, didn't dress up in costumes this year either. This provides us with a value for category 3, from which we can derive a value for category 2 (8). However, we still don't know how many of the 60 costume bearers from this year wore costumes last year.

Since this is an overlapping set problem, we could also have used a double-set matrix to organize our information and solve. Even with both statements together, we can not find the value for the Costume Last Year / Costume This Year cell.

Re: What percentage of the current fourth graders at Liberation [#permalink]

Show Tags

24 Nov 2014, 06:06

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. _________________

Re: What percentage of the current fourth graders at Liberation [#permalink]

Show Tags

12 Mar 2016, 20:27

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. _________________

Last year when I attended a session of Chicago’s Booth Live , I felt pretty out of place. I was surrounded by professionals from all over the world from major...

I recently returned from attending the London Business School Admits Weekend held last week. Let me just say upfront - for those who are planning to apply for the...