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

 It is currently 16 Jan 2019, 21:44

### 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 January
PrevNext
SuMoTuWeThFrSa
303112345
6789101112
13141516171819
20212223242526
272829303112
Open Detailed Calendar
• ### The winning strategy for a high GRE score

January 17, 2019

January 17, 2019

08:00 AM PST

09:00 AM PST

Learn the winning strategy for a high GRE score — what do people who reach a high score do differently? We're going to share insights, tips and strategies from data we've collected from over 50,000 students who used examPAL.
• ### Free GMAT Strategy Webinar

January 19, 2019

January 19, 2019

07:00 AM PST

09:00 AM PST

Aiming to score 760+? Attend this FREE session to learn how to Define your GMAT Strategy, Create your Study Plan and Master the Core Skills to excel on the GMAT.

# At a certain university, 7 students from the 10-student history depart

Author Message
TAGS:

### Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 52164
At a certain university, 7 students from the 10-student history depart  [#permalink]

### Show Tags

08 Apr 2016, 01:51
00:00

Difficulty:

35% (medium)

Question Stats:

82% (02:48) correct 18% (02:55) wrong based on 53 sessions

### HideShow timer Statistics

At a certain university, 7 students from the 10-student history department and 5 students from the 7-student English department will be selected to form a 12-student committee. At a neighboring university, 2 students from a 10-person math department and 3 students from a 7-student science department will be selected to form a 5-student focus group. What is the ratio of the number of ways in which the 12-student committee can be formed to the number of ways in which the 5-student focus group can be formed?

A. 25/16
B. 8/5
C. 12/5
D. 16/5
E. 144/25

_________________
SC Moderator
Joined: 13 Apr 2015
Posts: 1687
Location: India
Concentration: Strategy, General Management
GMAT 1: 200 Q1 V1
GPA: 4
WE: Analyst (Retail)
Re: At a certain university, 7 students from the 10-student history depart  [#permalink]

### Show Tags

08 Apr 2016, 20:21
Number of ways of selecting a 12 member student committee = 10C7 * 7C5
Number of ways of selecting a focus group of 5 students = 10C2 * 7C3

Ratio of 12 member student committee to 5 member focus group = $$\frac{10C7 * 7C5}{10C2 * 7C3}$$ = $$\frac{8}{5}$$

Intern
Joined: 18 May 2017
Posts: 12
Re: At a certain university, 7 students from the 10-student history depart  [#permalink]

### Show Tags

21 May 2017, 07:40
Vyshak wrote:
Number of ways of selecting a 12 member student committee = 10C7 * 7C5
Number of ways of selecting a focus group of 5 students = 10C2 * 7C3

Ratio of 12 member student committee to 5 member focus group = $$\frac{10C7 * 7C5}{10C2 * 7C3}$$ = $$\frac{8}{5}$$

Would you kindly clarify how you canceled the combinations and got 8/5 at the end?
Current Student
Joined: 04 Jan 2016
Posts: 166
Location: United States (NY)
GMAT 1: 620 Q44 V32
GMAT 2: 600 Q48 V25
GMAT 3: 660 Q42 V39
GPA: 3.48
Re: At a certain university, 7 students from the 10-student history depart  [#permalink]

### Show Tags

21 May 2017, 13:06
Michaelkalend13 wrote:
Vyshak wrote:
Number of ways of selecting a 12 member student committee = 10C7 * 7C5
Number of ways of selecting a focus group of 5 students = 10C2 * 7C3

Ratio of 12 member student committee to 5 member focus group = $$\frac{10C7 * 7C5}{10C2 * 7C3}$$ = $$\frac{8}{5}$$

Would you kindly clarify how you canceled the combinations and got 8/5 at the end?

It is going to be a long one, if you like it, don't forget to hit me with a kudos.

i) $$(\frac{10}{1}*\frac{9}{2}*\frac{8}{3}*\frac{7}{4}*\frac{6}{5}*\frac{5}{6}*\frac{4}{7})*(\frac{7}{1}*\frac{6}{2}*\frac{5}{3}*\frac{4}{4}*\frac{3}{5})=$$

ii) $$(\frac{10}{1}*\frac{9}{2})*(\frac{7}{1}*\frac{6}{2}*\frac{5}{3})=$$

Now, if you do the simplification and divide as $$\frac{i}{ii}$$ you will get $$\frac{8}{5}$$
Re: At a certain university, 7 students from the 10-student history depart &nbs [#permalink] 21 May 2017, 13:06
Display posts from previous: Sort by