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

 It is currently 18 Mar 2019, 10:55

### 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

# At a certain high school, the junior class is twice the size of the se

Author Message
TAGS:

### Hide Tags

Manager
Joined: 02 Jun 2011
Posts: 123
At a certain high school, the junior class is twice the size of the se  [#permalink]

### Show Tags

21 May 2012, 05:29
1
8
00:00

Difficulty:

25% (medium)

Question Stats:

79% (01:56) correct 21% (02:23) wrong based on 213 sessions

### HideShow timer Statistics

At a certain high school, the junior class is twice the size of the senior class. If 1/3 of the seniors & 1/4 of the juniors study Japanese, what fraction of the students in both classes do not study Japanese?

A. 1/6
B. 5/18
C. 5/12
D. 7/12
E. 13/18

Is it possible to do as follows?
1/3*s+1/4*2s = study japanese
then 5/6 * s = study japanese and 1/6 do not
why is this wrong?
Math Expert
Joined: 02 Sep 2009
Posts: 53657
Re: At a certain high school, the junior class is twice the size of the se  [#permalink]

### Show Tags

21 May 2012, 06:25
1
kashishh wrote:
At a certain high school, the junior class is twice the size of the senior class. If 1/3 of the seniors & 1/4 of the juniors study Japanese, what fraction of the students in both classes do not study Japanese?

A. 1/6
B. 5/18
C. 5/12
D. 7/12
E. 13/18

Is it possible to do as follows?
1/3*s+1/4*2s = study japanese
then 5/6 * s = study japanese and 1/6 do not
why is this wrong?

If we do the way you proposed then the # of the students that study Japanese is 1/3*s+1/4*2s=5s/6. Since the total # of the students is s+2s=3s then the # of the students that does not study Japanese is 3s-5s/6=13s/6, so fraction of the students that do not study Japanese is (13s/6)/3s=13/18.

Else you can do as follows: say there are 6 seniors and 2*6=12 juniors, so total of 6+12=18 students.

2/3 of the seniors do not study Japanese, so 2/3*6=4 seniors do not study Japanese;
3/4 of the juniors do not study Japanese, so 3/4*12=9 juniors do not study Japanese;

Total of 4+9=13 students do not study Japanese, which is 13/18 of all students.

Hope it helps.
_________________
SVP
Status: The Best Or Nothing
Joined: 27 Dec 2012
Posts: 1817
Location: India
Concentration: General Management, Technology
WE: Information Technology (Computer Software)
Re: At a certain high school, the junior class is twice the size of the se  [#permalink]

### Show Tags

02 Sep 2014, 23:11
Let strength of senior class = x

Strength of junior class = 2x

Total = 3x

Japanese Speaking$$= \frac{x}{2} + \frac{x}{3} = \frac{5x}{6}$$

Not Japanese speaking $$= 3x - \frac{5x}{6} = \frac{13x}{6}$$

Fraction $$= \frac{\frac{13x}{6}}{3x} = \frac{13}{18}$$

_________________

Kindly press "+1 Kudos" to appreciate

Manager
Joined: 23 Apr 2014
Posts: 62
Location: United States
GMAT 1: 680 Q50 V31
GPA: 2.75
Re: At a certain high school, the junior class is twice the size of the se  [#permalink]

### Show Tags

06 Dec 2016, 10:55
kashishh wrote:
At a certain high school, the junior class is twice the size of the senior class. If 1/3 of the seniors & 1/4 of the juniors study Japanese, what fraction of the students in both classes do not study Japanese?

A. 1/6
B. 5/18
C. 5/12
D. 7/12
E. 13/18

Is it possible to do as follows?
1/3*s+1/4*2s = study japanese
then 5/6 * s = study japanese and 1/6 do not
why is this wrong?

J = junior class size
S = senior class size
Total class size = J+S = 3S ( because J= 2S)

2/3 S and 3/4J don't study Japanese.
Total number not studying Japanese = (2/3)S + (3/4)J= (2/3)S + (3/4) * 2S
= (13/6)S

So required fraction = [(13/6)S]/3S = 13/18

Hope this helps.
Board of Directors
Status: QA & VA Forum Moderator
Joined: 11 Jun 2011
Posts: 4394
Location: India
GPA: 3.5
Re: At a certain high school, the junior class is twice the size of the se  [#permalink]

### Show Tags

06 Dec 2016, 11:05
kashishh wrote:
At a certain high school, the junior class is twice the size of the senior class. If 1/3 of the seniors & 1/4 of the juniors study Japanese, what fraction of the students in both classes do not study Japanese?

A. 1/6
B. 5/18
C. 5/12
D. 7/12
E. 13/18

Let the no of students in Senior Class be 6
So, the no of students in Junior Class be 12

Total No of Students is 18

So, 2 students of Senior Class study Japanese
And, 3 students of Junior Class study Japanese

Students who study Japanese is 5

Hence, 13 students do not study Japanese.

Thus, fraction of the students in both classes do not study Japanese is 13/18

Hence, answer will be (E) 13/18
_________________

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 )

VP
Joined: 09 Mar 2016
Posts: 1277
At a certain high school, the junior class is twice the size of the se  [#permalink]

### Show Tags

06 Oct 2018, 07:31
kashishh wrote:
At a certain high school, the junior class is twice the size of the senior class. If 1/3 of the seniors & 1/4 of the juniors study Japanese, what fraction of the students in both classes do not study Japanese?

A. 1/6
B. 5/18
C. 5/12
D. 7/12
E. 13/18

Is it possible to do as follows?
1/3*s+1/4*2s = study japanese
then 5/6 * s = study japanese and 1/6 do not
why is this wrong?

Let there be 60 junior and 30 senior students

hence 1/3*3 = 10 and 1/4*60 = 15

so 25 students study Japenese

90-25 =65 students who dont study japanese

65/90 i.e 13/18 is fraction of the students in both classes do not study Japanese
At a certain high school, the junior class is twice the size of the se   [#permalink] 06 Oct 2018, 07:31
Display posts from previous: Sort by