French and Japanese (GMAT PREP 1)

This topic has expert replies
Master | Next Rank: 500 Posts
Posts: 435
Joined: Wed Nov 16, 2011 7:27 am
Thanked: 48 times
Followed by:16 members

French and Japanese (GMAT PREP 1)

by alex.gellatly » Fri Aug 03, 2012 10:56 pm
At least 100 students at a certain high school study Japanese. If 4 percent of the students at the school who study French also study Japanese, do more students at the school study French than Japanese?

1. 16 students at the school study both French and Japanese.
2. 10 percent of the students at the school who study Japanese also study French.

Thanks!
A useful website I found that has every quant OG video explanation:

https://www.beatthegmat.com/useful-websi ... tml#475231
Source: — Data Sufficiency |

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 3835
Joined: Fri Apr 02, 2010 10:00 pm
Location: Milpitas, CA
Thanked: 1854 times
Followed by:523 members
GMAT Score:770

by Anurag@Gurome » Sat Aug 04, 2012 3:32 am
alex.gellatly wrote:At least 100 students at a certain high school study Japanese. If 4 percent of the students at the school who study French also study Japanese, do more students at the school study French than Japanese?

1. 16 students at the school study both French and Japanese.
2. 10 percent of the students at the school who study Japanese also study French.

Thanks!
Say, number of students studying Japanese = J and number of students studying French = F. Now, J ≥ 100 and 4% of F study both Japanese and French.

Statement 1: 16 students at the school study both French and Japanese.
Therefore, 4% of F = 16
=> F = (16/0.04) = 400
As we don't have any concrete idea about the value of J, we cannot say whether F is greater than J or not.

Not sufficient

Statement 2: 10 percent of the students at the school who study Japanese also study French.
Therefore, 4% of F = 10% of J
=> F = J*(0.10)/(0.04) = (2.5)*J
=> F > J

Sufficient

The correct answer is B.
Anurag Mairal, Ph.D., MBA
GMAT Expert, Admissions and Career Guidance
Gurome, Inc.
1-800-566-4043 (USA)

Join Our Facebook Groups
GMAT with Gurome
https://www.facebook.com/groups/272466352793633/
Admissions with Gurome
https://www.facebook.com/groups/461459690536574/
Career Advising with Gurome
https://www.facebook.com/groups/360435787349781/

User avatar
Master | Next Rank: 500 Posts
Posts: 210
Joined: Thu Mar 08, 2012 11:24 pm
Thanked: 62 times
Followed by:3 members

by niketdoshi123 » Sat Aug 04, 2012 3:33 am
del

User avatar
GMAT Instructor
Posts: 349
Joined: Wed Sep 28, 2011 3:38 pm
Location: Austin, TX
Thanked: 236 times
Followed by:54 members
GMAT Score:770

by GmatMathPro » Sat Aug 04, 2012 6:10 am
alex.gellatly wrote:At least 100 students at a certain high school study Japanese. If 4 percent of the students at the school who study French also study Japanese, do more students at the school study French than Japanese?

1. 16 students at the school study both French and Japanese.
2. 10 percent of the students at the school who study Japanese also study French.

Thanks!
Also, note that "students who study French that also study Japanese" (as paraphrased from the question) and "students who study Japanese that also study French" (as paraphrased from statement 2) both refer to the same quantity: the number of students who study both subjects. You can also think of them as both referring to the overlapping portion of the Venn diagram. Statement 2 tells us that this quantity is a BIGGER portion of the students that study Japanese (10%) than it is of the students who study French(4%). Thus, more students must study French.
Pete Ackley
GMAT Math Pro
Free Online Tutoring Trial