Events & Promotions
|
|
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
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Apr 2808:00 AM PDT
-11:00 AM PDT
Whether you are just beginning your MBA journey or fine-tuning your path to a 700+ score, GMAT Day is designed to give you a competitive edge.
27 Jun 2019, 17:32
Kudos
Bookmarks
E
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
75%
(hard)
Question Stats:
59% (02:37) correct
41%
(02:50)
wrong
based on 304
sessions
History
Date
Time
Result
Not Attempted Yet
There are 10 students in a class. A student is allowed to shake hand only once with a student who is taller than him or equal in height to him. He can’t shake hand with anyone who is shorter than him. Average height of the class is 5 feet. What is the difference between the maximum and minimum number of handshakes that can take place in the class?
A. 20
B. 25
C. 30
D. 35
E. 45
A. 20
B. 25
C. 30
D. 35
E. 45
28 Jun 2019, 01:31
Kudos
Bookmarks
nick1816
Maximum number of handshakes = when all students are of the same height (they can all shake hands with each other, without any restriction on anybody) = 10C2 = 45
Minimum number of handshakes = when all students are of different heights (no one can shake hands with anyone (please forgive me for the SC error, if any) since it's stated that there is a constraint that no taller student can shake hands with a shorter student, so if no one is equal in height, of any pair of boys we choose to shake hands with each other - one will be taller / shorter than the other, which prohibits them from shaking hands) = 0
Answer = Maximum - Minimum = 45-0 = 45 (E)
Simple and short
General Discussion
28 Jun 2019, 01:55
Kudos
Bookmarks
nick1816
Good trap question.
Maximum is when all are 5 feet= 10C2=45
Minimum is when all are of different height then 0 shakes cause the shorter person cannot shake hands with a taller guy as he will be shorter to the taller guy ( didn’t realize it and arrived at 45 shakes here too and wasted time)
Posted from my mobile device
