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 2610:00 AM EDT
-11:00 AM EDT
The Target Test Prep course represents a quantum leap forward in GMAT preparation, a radical reinterpretation of the way that students should study. Try before you buy with a 5-day, full-access trial of the course for FREE!
Apr 2711:00 AM EDT
-12:00 PM EDT
Prefer video-based learning? The Target Test Prep OnDemand course is a one-of-a-kind video masterclass featuring 400 hours of lecture-style teaching by Scott Woodbury-Stewart, founder of Target Test Prep and one of the most accomplished GMAT instructors
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.
Updated on: 18 Nov 2019, 15:05
Originally posted by BrentGMATPrepNow on 18 Nov 2019, 09:52.
Last edited by BrentGMATPrepNow on 18 Nov 2019, 15:05, edited 1 time in total.
Last edited by BrentGMATPrepNow on 18 Nov 2019, 15:05, edited 1 time in total.
Kudos
Bookmarks
A
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:
57% (02:16) correct
43%
(02:09)
wrong
based on 221
sessions
History
Date
Time
Result
Not Attempted Yet
Three different vertices are randomly selected from a regular hexagon. If the three selected vertices are connected by lines to form a triangle, what is the probability that the resulting triangle has exactly two sides of equal length?
A) 0.3
B) 0.4
C) 0.5
D) 0.6
E) 0.7
A) 0.3
B) 0.4
C) 0.5
D) 0.6
E) 0.7
Every tricky question should trigger a follow up quiz.
Build that habit with
GMAT Club Forum Quiz →.
20 Nov 2019, 03:30
Kudos
Bookmarks
We are given a regular hexagon and are being asked to find the probability of selecting a triangle with exactly two equal sides using any three of the six vertices.
The "exactly two sides" detail is very important, as this piece of information eliminates triangles that have no equal sides and equilateral triangles.
Looking at a regular hexagon, we notice that we can form an isosceles triangle by connecting any vertex to its two immediate adjacent vertices (i.e., the vertices surrounding it). As we have 6 vertices, we can derive 6 triangles with exactly two equal sides following this method.
Now, let's try to connect a vertex to the next two vertices after the immediate adjacent vertices. We will notice once again, that each vertex forms 1 triangle. Therefore, we will have 6 triangles in total. However, if we pay close attention, we will realize that such triangles are equilaterals. Therefore, they have 3 equal sides, not exactly two sides. Hence, we can we cannot count them in.
Now that we have exhausted all the possibilities. We can calculate the number of triangles that can be formed with 6 vertices. 6C3 = 20.
In order to find the probability, we divide the number of possible triangles with exactly two sides over the number of all possible triangles, which gives us 6/20 or 0.3. Answer choice A.
The "exactly two sides" detail is very important, as this piece of information eliminates triangles that have no equal sides and equilateral triangles.
Looking at a regular hexagon, we notice that we can form an isosceles triangle by connecting any vertex to its two immediate adjacent vertices (i.e., the vertices surrounding it). As we have 6 vertices, we can derive 6 triangles with exactly two equal sides following this method.
Now, let's try to connect a vertex to the next two vertices after the immediate adjacent vertices. We will notice once again, that each vertex forms 1 triangle. Therefore, we will have 6 triangles in total. However, if we pay close attention, we will realize that such triangles are equilaterals. Therefore, they have 3 equal sides, not exactly two sides. Hence, we can we cannot count them in.
Now that we have exhausted all the possibilities. We can calculate the number of triangles that can be formed with 6 vertices. 6C3 = 20.
In order to find the probability, we divide the number of possible triangles with exactly two sides over the number of all possible triangles, which gives us 6/20 or 0.3. Answer choice A.
21 Nov 2019, 06:11
Kudos
Bookmarks
Total possibilities = 6C3 = 20 outcomes in total
Each vertex can be combined with 2 more vertex only thrice in unique combinations. For example in a hexagon labeled ABCDEF - These are the unique combinations - ABC, AFE, BCD, BAF, CDE and DEF. Hence probability is : 6/20 or 0.3
Each vertex can be combined with 2 more vertex only thrice in unique combinations. For example in a hexagon labeled ABCDEF - These are the unique combinations - ABC, AFE, BCD, BAF, CDE and DEF. Hence probability is : 6/20 or 0.3
