BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

Eurovision permutations (650+)

Expert replies
by Night reader » Sat Dec 04, 2010 8:15 pm
Mark is a hotel administrator, and he is making room reservations for five participants of the Eurovision song contest. The number of rooms available for the participants is five on the fifth-room floor; the contest manager requires Mark to accommodate all participants so that no male participant's room neighbors other male participant's one. In how many ways can Mark arrange five rooms among three male and two female participants?

A. 24
B. 16
C. 12
D. 48
E. 30
Join the discussion
Source: — Problem Solving |

by beat_gmat_09 » Sat Dec 04, 2010 8:22 pm
Night reader wrote:Mark is a hotel administrator, and he is making room reservations for five participants of the Eurovision song contest. The number of rooms available for the participants is five on the fifth-room floor; the contest manager requires Mark to accommodate all participants so that no male participant's room neighbors other male participant's one. In how many ways can Mark arrange five rooms among three male and two female participants?

A. 24
B. 16
C. 12
D. 48
E. 30
Question asks how many ways to arrange - MFMFM
No. of ways - 3*2*2*1*1 = 12
Hope is the dream of a man awake
Join the discussion

by Night reader » Sat Dec 04, 2010 8:25 pm
Viva!

correct answer C.
thanks
Join the discussion

by Rahul@gurome » Sat Dec 04, 2010 8:27 pm
This means that if the rooms are numbered 1 to 5, the males will occupy first, third and fifth rooms and the females will occupy second or fourth rooms.
The number of ways this can be done is 3!*2! = 12.
The correct answer is C.
Rahul Lakhani
Quant Expert
Gurome, Inc.
https://www.GuroMe.com
On MBA sabbatical (at ISB) for 2011-12 - will stay active as time permits
1-800-566-4043 (USA)
+91-99201 32411 (India)
Join the discussion

by Night reader » Sat Dec 04, 2010 8:28 pm
Rahul@gurome wrote:This means that if the rooms are numbered 1 to 5, the males will occupy first, third and fifth rooms and the females will occupy second or fourth rooms.
The number of ways this can be done is 3!*2! = 12.
The correct answer is C.
Rahul, I found it more useful to work with diagrams for permutations rather going through combining and separating events:

___.....___.....___.....___.....___......___
F(3).....M(2).....F(2)....M(1)....F(1).....M(1)

3*2*2*1*1*1=12
Join the discussion

by goyalsau » Sun Dec 05, 2010 2:02 am
Night reader wrote:
no male participant's room neighbors other male participant's one.
There was a time when its said No female participant will neighbor Male Participant, But Now everything is changed, POOR GIRLS........ :D
Saurabh Goyal
[email protected]
-------------------------


EveryBody Wants to Win But Nobody wants to prepare for Win.
Join the discussion