Each of the students in a certain class received a single : GMAT Data Sufficiency (DS)
Check GMAT Club Decision Tracker for the Latest School Decision Releases http://gmatclub.com/AppTrack

 It is currently 18 Jan 2017, 05:16

### 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

# Each of the students in a certain class received a single

Author Message
TAGS:

### Hide Tags

Director
Joined: 03 Sep 2006
Posts: 879
Followers: 6

Kudos [?]: 769 [2] , given: 33

Each of the students in a certain class received a single [#permalink]

### Show Tags

03 Jun 2007, 02:08
2
KUDOS
7
This post was
BOOKMARKED
00:00

Difficulty:

15% (low)

Question Stats:

72% (01:43) correct 28% (00:52) wrong based on 412 sessions

### HideShow timer Statistics

Each of the students in a certain class received a single grade of P, F,or I.What percent of the students in the class were females?

(1) Of those who received a P, 40 percent were females.
(1) Of those who received either an F or I, 80 percent were males.
[Reveal] Spoiler: OA
Director
Joined: 03 Sep 2006
Posts: 879
Followers: 6

Kudos [?]: 769 [0], given: 33

### Show Tags

03 Jun 2007, 15:28
Himalayan wrote:
LM wrote:
Each of the students in a certain class received a single grade of P,F,or I.What percent of the students in the class were females?

( i ) Of those who received a P, 40 percent were females.

( ii ) Of those who received either an F or I, 80 percent were males.

Could some explain with the help of Venn Diagrams???

seems E for me.

yeah, it is E. Could you please explain? ( Did you use Venn Diagrams? )
Manager
Joined: 04 May 2007
Posts: 110
Followers: 1

Kudos [?]: 1 [0], given: 0

### Show Tags

03 Jun 2007, 15:55
LM

I started to use Venn but there was no point IMHO.

We don't know what P or F or I represent. no proportion of the total class was given.

does 40% of P represent 10% of the entire class? 90% of the class?

what does 20% of F or I represent of the total percentage of the class? we dont know. maybe my reasoning is wrong, but that is how I came up with my answer: E
Manager
Joined: 02 Jan 2007
Posts: 208
Followers: 2

Kudos [?]: 8 [2] , given: 0

### Show Tags

04 Jun 2007, 07:58
2
KUDOS
Sometimes making a table is easier than getting into Venn diagrams.

I found it easy to get to E after I filled in the empty boxes and still couldnt say I had sufficient information.
Attachments

DS_table.gif [ 1.66 KiB | Viewed 12654 times ]

Director
Joined: 03 Sep 2006
Posts: 879
Followers: 6

Kudos [?]: 769 [0], given: 33

### Show Tags

04 Jun 2007, 17:13
vikramjit_01 wrote:
Sometimes making a table is easier than getting into Venn diagrams.

I found it easy to get to E after I filled in the empty boxes and still couldnt say I had sufficient information.

Thanks! This is what I was looking for in form of either table or venn diagram!
Intern
Joined: 28 Apr 2013
Posts: 16
GMAT Date: 08-03-2013
GPA: 3.3
WE: Supply Chain Management (Military & Defense)
Followers: 0

Kudos [?]: 11 [0], given: 3

Re: Each of the students in a certain class received a single [#permalink]

### Show Tags

07 Jun 2013, 19:34
So taking 1&2 together we know 80% of those with a fail/incomplete were male so 20% with F&I were female correct? If 40% of those who passed were female, then we can determine that 30% of the students were female.

This was my rationale towards an answer of C. Can anyone explain where I went wrong?
Math Expert
Joined: 02 Sep 2009
Posts: 36540
Followers: 7074

Kudos [?]: 93076 [3] , given: 10542

Re: Each of the students in a certain class received a single [#permalink]

### Show Tags

08 Jun 2013, 03:42
3
KUDOS
Expert's post
4
This post was
BOOKMARKED
Nwsmith11 wrote:
Each of the students in a certain class received a single grade of P, F,or I.What percent of the students in the class were females?

(1) Of those who received a P, 40 percent were females.
(1) Of those who received either an F or I, 80 percent were males.

So taking 1&2 together we know 80% of those with a fail/incomplete were male so 20% with F&I were female correct? If 40% of those who passed were female, then we can determine that 30% of the students were female.

This was my rationale towards an answer of C. Can anyone explain where I went wrong?

No, the correct answer is E. Consider the following examples:

P=50 and F+I=50, then the # of females = 0.4*50 + 0.2*50 = 30.
P=10 and F+I=90, then the # of females = 0.4*10 + 0.2*90 = 22.

Hope it's clear.
_________________
Senior Manager
Joined: 21 Jan 2010
Posts: 344
Followers: 2

Kudos [?]: 176 [0], given: 12

### Show Tags

08 Jun 2013, 17:24
vikramjit_01 wrote:
Sometimes making a table is easier than getting into Venn diagrams.

I found it easy to get to E after I filled in the empty boxes and still couldnt say I had sufficient information.

Current Student
Joined: 06 Sep 2013
Posts: 2035
Concentration: Finance
GMAT 1: 770 Q0 V
Followers: 62

Kudos [?]: 593 [0], given: 355

Re: Each of the students in a certain class received a single [#permalink]

### Show Tags

17 Oct 2013, 05:49
LM wrote:
Each of the students in a certain class received a single grade of P, F,or I.What percent of the students in the class were females?

(1) Of those who received a P, 40 percent were females.
(1) Of those who received either an F or I, 80 percent were males.

Yup, its E. We can't assume that P,F or I are equally weighted.
GMAT Club Legend
Joined: 09 Sep 2013
Posts: 13436
Followers: 575

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

Re: Each of the students in a certain class received a single [#permalink]

### Show Tags

03 Jan 2015, 20:12
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.
_________________
Intern
Joined: 20 Dec 2014
Posts: 21
Followers: 0

Kudos [?]: 2 [1] , given: 25

Re: Each of the students in a certain class received a single [#permalink]

### Show Tags

17 Mar 2015, 09:47
1
KUDOS
Takeaways: This one was a bit tricky because I approached the problem as a double matrix set but it had 3 variables in the columns and 2 variables(male/female) in the rows. I also attempted to do percentages that lead up to a total but it was getting more complex than I would like. What has helped was recognizing this as a weighted average problem. Therefore an easy method could be:
T (total) = F + P +I
Since we have male and female : T=(M)F+(F)F+(M)P+(F)P+(M)I+(F)I or organize like this T=(M)F+(M)P+(M)I+(F)F+(F)P+(F)I
Translating the statement word by word I got (W/100)T= F? which is the main question we are looking to answer but made it easier on myself by just writing (F/T)*100%=?
1. Of those who received a P, 40% were females
This is clearly insufficient because (F)(P)= .4P and (M)(P)= .6P does not give us any actual numbers to plug in and we still need the other weighted averages.

2. Of those who received either an F or I , 80% were males.
T=.8F+.2F+ (M)P+(F)P+(.8)I+(.2)I
Insufficient because we need actual numbers because weighted averages depend on quantities

(1) and (2)
Insufficient because although we have several percentages we still need quantities because we can have 80/100 total students in f and I be males but then have 4/10 students in P be women.

Bunuel - thoughts?
EMPOWERgmat Instructor
Status: GMAT Assassin/Co-Founder
Affiliations: EMPOWERgmat
Joined: 19 Dec 2014
Posts: 8279
Location: United States (CA)
GMAT 1: 800 Q51 V49
GRE 1: 340 Q170 V170
Followers: 380

Kudos [?]: 2458 [0], given: 163

Re: Each of the students in a certain class received a single [#permalink]

### Show Tags

18 Mar 2015, 19:10
Hi GMAT01,

You ARE correct. When dealing with these type of broad percent-based questions, it's important to be a bit cynical. You do NOT know how many students are in each subgroup, so it would take a LOT of information to answer this question.

As an example, when Fact 1 tells us "Of those who received a P, 40 percent were females", we don't know if 5 people got a P (in which 2 of them were female) or 500 people got a P (in which 200 of them were female). Making the individual group numbers relatively big or relatively small will impact the overall calculation. This can save you some time and effort.

GMAT assassins aren't born, they're made,
Rich
_________________

# Rich Cohen

Co-Founder & GMAT Assassin

# Special Offer: Save \$75 + GMAT Club Tests

60-point improvement guarantee
www.empowergmat.com/

***********************Select EMPOWERgmat Courses now include ALL 6 Official GMAC CATs!***********************

Intern
Joined: 08 Feb 2014
Posts: 8
Location: United States
Concentration: Marketing, Operations
GMAT 1: 580 Q36 V34
WE: Information Technology (Computer Software)
Followers: 0

Kudos [?]: 6 [0], given: 26

Re: Each of the students in a certain class received a single [#permalink]

### Show Tags

20 Sep 2015, 20:02
1
This post was
BOOKMARKED
Bunuel wrote:
Nwsmith11 wrote:
Each of the students in a certain class received a single grade of P, F,or I.What percent of the students in the class were females?

(1) Of those who received a P, 40 percent were females.
(1) Of those who received either an F or I, 80 percent were males.

So taking 1&2 together we know 80% of those with a fail/incomplete were male so 20% with F&I were female correct? If 40% of those who passed were female, then we can determine that 30% of the students were female.

This was my rationale towards an answer of C. Can anyone explain where I went wrong?

No, the correct answer is E. Consider the following examples:

P=50 and F+I=50, then the # of females = 0.4*50 + 0.2*50 = 30.
P=10 and F+I=90, then the # of females = 0.4*10 + 0.2*90 = 22.

Hope it's clear.

@Bunnel - Is it safe to say that in these type of questions until we get the entire class strength in either of the statements, we would always choose E. As stated in your example, we are plugging different set of values and getting different set of answers.

Thanks.
GMAT Club Legend
Joined: 09 Sep 2013
Posts: 13436
Followers: 575

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

Re: Each of the students in a certain class received a single [#permalink]

### Show Tags

23 Oct 2016, 00:31
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: Each of the students in a certain class received a single   [#permalink] 23 Oct 2016, 00:31
Similar topics Replies Last post
Similar
Topics:
9 Of the 250 students in a certain class, each student who majors in 6 08 Jul 2015, 04:35
3 At a certain picnic, each of the guests was served either a single 9 21 Jun 2011, 11:47
3 If each of the students in a certain mathematics class is 3 23 Aug 2010, 07:54
11 Of the students in a certain class, 55% of the female and 13 29 Mar 2009, 09:59
40 Of the students who eat in a certain cafeteria, each student 8 25 Dec 2007, 06:27
Display posts from previous: Sort by