• 7 CATs FREE!
    If you earn 100 Forum Points

    Engage in the Beat The GMAT forums to earn
    100 points for $49 worth of Veritas practice GMATs FREE

    Veritas Prep
    VERITAS PRACTICE GMAT EXAMS
    Earn 10 Points Per Post
    Earn 10 Points Per Thanks
    Earn 10 Points Per Upvote
    REDEEM NOW

A group of medical interns at Bohemus Medical School want to

This topic has 4 expert replies and 0 member replies

A group of medical interns at Bohemus Medical School want to

Post

Timer

00:00

Your Answer

A

B

C

D

E

Global Stats

Difficult



A group of medical interns at Bohemus Medical School want to go on dates. There are 5
girls and 5 guys. Assuming girls go on dates with guys, how many possible ways can these
10 medical interns date each other?

(A)
10

(B)
25

(C)
60

(D)
90

(E)
120

  • +1 Upvote Post
  • Quote
  • Flag

GMAT/MBA Expert

Post
subh2273 wrote:
A group of medical interns at Bohemus Medical School want to go on dates. There are 5
girls and 5 guys. Assuming girls go on dates with guys, how many possible ways can these
10 medical interns date each other?

(A)
10

(B)
25

(C)
60

(D)
90

(E)
120
In other words:
How many ways can 5 girls and 5 guys be divided into pairs, if each pair must consist of one girl and one guy?

Number of options for the first girl = 5. (Any of the 5 guys.)
Number of options for the second girl = 4. (Any of the 4 remaining guys).
Number of options for the third girl = 3. (Any of the 3 remaining guys.)
Number of options for the fourth girl = 2. (Either of the 2 remaining guys.)
Number of options for the fifth girl = 1. (Only one guy left.)
To combine the options above, we multiply:
5*4*3*2*1 = 120.

The correct answer is E.

_________________
Mitch Hunt
Private Tutor for the GMAT and GRE
GMATGuruNY@gmail.com

If you find one of my posts helpful, please take a moment to click on the "UPVOTE" icon.

Available for tutoring in NYC and long-distance.
For more information, please email me at GMATGuruNY@gmail.com.
Student Review #1
Student Review #2
Student Review #3

  • +1 Upvote Post
  • Quote
  • Flag
Free GMAT Practice Test How can you improve your test score if you don't know your baseline score? Take a free online practice exam. Get started on achieving your dream score today! Sign up now.

GMAT/MBA Expert

Post
subh2273 wrote:
A group of medical interns at Bohemus Medical School want to go on dates. There are 5
girls and 5 guys. Assuming girls go on dates with guys, how many possible ways can these
10 medical interns date each other?

(A)
10

(B)
25

(C)
60

(D)
90

(E)
120
Take the task of arranging dates and break it into stages.

Let A, B, C, D and E represent the 5 girls

Stage 1: Select a boy to date girl A
We can choose any of the 5 boys, so we can complete stage 1 in 5 ways

Stage 2: Select a boy to date girl B
Since we already selected a boy in stage 1, there are 4 boys remaining to choose from.
So we can complete stage 2 in 4 ways

Stage 3: Select a boy to date girl C
There are 3 boys remaining to choose from.
So we can complete stage 3 in 3 ways

Stage 4: Select a boy to date girl D
2 boys remaining. So we can complete stage 4 in 2 ways

Stage 5: Select a boy to date girl E
There is 1 boy remaining to be seated, so we can complete stage 5 in 1 way

By the Fundamental Counting Principle (FCP), we can complete all 5 stages (and thus arrange all dates) in (5)(4)(3)(2)(1) ways (= 120 ways)

Answer: E

Note: the FCP can be used to solve the MAJORITY of counting questions on the GMAT. For more information about the FCP, watch our free video: http://www.gmatprepnow.com/module/gmat-counting/video/775

You can also watch a demonstration of the FCP in action: https://www.gmatprepnow.com/module/gmat-counting/video/776

Then you can try solving the following questions:

EASY
- https://www.beatthegmat.com/what-should-be-the-answer-t267256.html
- https://www.beatthegmat.com/counting-problem-company-recruitment-t244302.html
- https://www.beatthegmat.com/picking-a-5-digit-code-with-an-odd-middle-digit-t273110.html
- https://www.beatthegmat.com/permutation-combination-simple-one-t257412.html
- https://www.beatthegmat.com/simple-one-t270061.html


MEDIUM
- https://www.beatthegmat.com/combinatorics-solution-explanation-t273194.html
- https://www.beatthegmat.com/arabian-horses-good-one-t150703.html
- https://www.beatthegmat.com/sub-sets-probability-t273337.html
- https://www.beatthegmat.com/combinatorics-problem-t273180.html
- https://www.beatthegmat.com/digits-numbers-t270127.html
- https://www.beatthegmat.com/doubt-on-separator-method-t271047.html
- https://www.beatthegmat.com/combinatorics-problem-t267079.html


DIFFICULT
- https://www.beatthegmat.com/wonderful-p-c-ques-t271001.html
- https://www.beatthegmat.com/permutation-and-combination-t273915.html
- https://www.beatthegmat.com/permutation-t122873.html
- https://www.beatthegmat.com/no-two-ladies-sit-together-t275661.html
- https://www.beatthegmat.com/combinations-t123249.html


Cheers,
Brent

_________________
Brent Hanneson – Creator of GMATPrepNow.com
Use our video course along with Beat The GMAT's free 60-Day Study Guide

Sign up for our free Question of the Day emails
And check out all of our free resources

  • +1 Upvote Post
  • Quote
  • Flag
GMAT Prep Now's comprehensive video course can be used in conjunction with Beat The GMAT’s FREE 60-Day Study Guide and reach your target score in 2 months!
Post
subh2273 wrote:
A group of medical interns at Bohemus Medical School want to go on dates. There are 5
girls and 5 guys. Assuming girls go on dates with guys, how many possible ways can these
10 medical interns date each other?
$$(A) 10 \,\,\,\,\,\,\,\,\,\,\, (B) 25 \,\,\,\,\,\,\,\,\,\,\, (C) 60 \,\,\,\,\,\,\,\,\,\,\, (D) 90 \,\,\,\,\,\,\,\,\,\,\, (E) 120$$
\[?\,\,\,\,:\,\,\,\,\# \,\,\,{\text{guy - girl}}\,\,{\text{pairs}}\]
Imagine girls in a row (say) in alphabetical order.

FOCUS: number of ways to put 5 guys in a row (parallel to the first row, each guy facing one girl - this is a pair!)
\[?\, = \,{P_{\,5}}\,\, = 5! = 120\]

This solution follows the notations and rationale taught in the GMATH method.

Regards,
Fabio.

_________________
Fabio Skilnik :: https://GMATH.net (Math for the GMAT)
Testimonials :: https://GMATH.net/testimonials.html
Course release PROMO : finish our test drive till 31/Oct with (at least) 60 correct answers out of 92 (12-questions Mock included) to gain a 60% discount!

  • +1 Upvote Post
  • Quote
  • Flag
Post
subh2273 wrote:
A group of medical interns at Bohemus Medical School want to go on dates. There are 5
girls and 5 guys. Assuming girls go on dates with guys, how many possible ways can these
10 medical interns date each other?

(A)
10

(B)
25

(C)
60

(D)
90

(E)
120
The first girl has 5 choices of guys, the second girl has 4 choices of guys (after a guy is picked by the first girl), the third girl has 3 choices of guys (after a guy is picked by the second girl), and so on. So the number of ways these 10 interns can date each other is 5 x 4 x 3 x 2 x 1 = 120.

Answer: E

_________________
Scott Woodbury-Stewart Founder and CEO

  • +1 Upvote Post
  • Quote
  • Flag
  • EMPOWERgmat Slider
    1 Hour Free
    BEAT THE GMAT EXCLUSIVE

    Available with Beat the GMAT members only code

    MORE DETAILS
    EMPOWERgmat Slider
  • Kaplan Test Prep
    Free Practice Test & Review
    How would you score if you took the GMAT

    Available with Beat the GMAT members only code

    MORE DETAILS
    Kaplan Test Prep
  • Veritas Prep
    Free Veritas GMAT Class
    Experience Lesson 1 Live Free

    Available with Beat the GMAT members only code

    MORE DETAILS
    Veritas Prep
  • Magoosh
    Magoosh
    Study with Magoosh GMAT prep

    Available with Beat the GMAT members only code

    MORE DETAILS
    Magoosh
  • Target Test Prep
    5-Day Free Trial
    5-day free, full-access trial TTP Quant

    Available with Beat the GMAT members only code

    MORE DETAILS
    Target Test Prep
  • Varsity Tutors
    Award-winning private GMAT tutoring
    Register now and save up to $200

    Available with Beat the GMAT members only code

    MORE DETAILS
    Varsity Tutors
  • The Princeton Review
    FREE GMAT Exam
    Know how you'd score today for $0

    Available with Beat the GMAT members only code

    MORE DETAILS
    The Princeton Review
  • Economist Test Prep
    Free Trial & Practice Exam
    BEAT THE GMAT EXCLUSIVE

    Available with Beat the GMAT members only code

    MORE DETAILS
    Economist Test Prep
  • PrepScholar GMAT
    5 Day FREE Trial
    Study Smarter, Not Harder

    Available with Beat the GMAT members only code

    MORE DETAILS
    PrepScholar GMAT
  • e-gmat Exclusive Offer
    Get 300+ Practice Questions
    25 Video lessons and 6 Webinars for FREE

    Available with Beat the GMAT members only code

    MORE DETAILS
    e-gmat Exclusive Offer

Top First Responders*

1 fskilnik@GMATH 74 first replies
2 Jay@ManhattanReview 49 first replies
3 Brent@GMATPrepNow 47 first replies
4 GMATGuruNY 43 first replies
5 Rich.C@EMPOWERgma... 36 first replies
* Only counts replies to topics started in last 30 days
See More Top Beat The GMAT Members

Most Active Experts

1 image description fskilnik@GMATH

GMATH Teacher

195 posts
2 image description Scott@TargetTestPrep

Target Test Prep

183 posts
3 image description Brent@GMATPrepNow

GMAT Prep Now Teacher

123 posts
4 image description Max@Math Revolution

Math Revolution

89 posts
5 image description GMATGuruNY

The Princeton Review Teacher

87 posts
See More Top Beat The GMAT Experts