Find all School-related info fast with the new School-Specific MBA Forum

It is currently 25 May 2015, 10:24

Today:

Free Access to GMAT Club Tests - May 25th for Memorial Day!!


Close

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
Your Progress

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

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

What is the perimeter of isosceles triangle MNP?

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
Expert Post
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 27493
Followers: 4312

Kudos [?]: 42288 [0], given: 6012

What is the perimeter of isosceles triangle MNP? [#permalink] New post 14 Jun 2012, 02:13
Expert's post
4
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  15% (low)

Question Stats:

66% (01:35) correct 34% (00:26) wrong based on 360 sessions
Expert Post
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 27493
Followers: 4312

Kudos [?]: 42288 [0], given: 6012

Re: What is the perimeter of isosceles triangle MNP? [#permalink] New post 14 Jun 2012, 02:14
Expert's post
SOLUTION

What is the perimeter of isosceles triangle MNP?

(1) MN = 16. We only know the length of one side. Not sufficient.
(2) NP = 20. We only know the length of one side. Not sufficient.

(1)+(2) If MN=MP=16 and NP=20 then the perimeter would be 16+16+20=52 but if MN=16 and NP=MP=20 then the perimeter would be 16+20+20=56. Not sufficient.

Answer: E.

Similar question to practice: what-is-the-perimeter-of-isosceles-triangle-mnp-134505.html#p1096591
_________________

NEW TO MATH FORUM? PLEASE READ THIS: ALL YOU NEED FOR QUANT!!!

PLEASE READ AND FOLLOW: 11 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory; 7. Remainders; 8. Overlapping Sets; 9. PDF of Math Book; 10. Remainders; 11. GMAT Prep Software Analysis NEW!!!; 12. SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) NEW!!!; 12. Tricky questions from previous years. NEW!!!;

COLLECTION OF QUESTIONS:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS ; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
25 extra-hard Quant Tests

GMAT Club Premium Membership - big benefits and savings

Senior Manager
Senior Manager
User avatar
Joined: 28 Mar 2012
Posts: 287
Concentration: Entrepreneurship
GMAT 1: 640 Q50 V26
GMAT 2: 660 Q50 V28
GMAT 3: 730 Q50 V38
Followers: 17

Kudos [?]: 206 [0], given: 23

GMAT ToolKit User
Re: What is the perimeter of isosceles triangle MNP? [#permalink] New post 14 Jun 2012, 03:16
Hi,

Difficulty level: close to 600. ('cause at first glance, I said, answer is (C). Then, when I actually solved, I got the right answer.)

Perimeter of isosceles triangle MNP?

Using (1),
MN = 16, no idea about NP & MP. Insufficient.

Using (2)
NP = 20, no idea about MN & MP. Insufficient.

Combining both the statements,
MN = 16 & NP = 20
for MNP to be isosceles, the third side MP can be 16 or 20. Insufficient.

Thus, Answer is (E).

Regards,
_________________

My posts: Solving Inequalities, Solving Simultaneous equations, Divisibility Rules

My story: 640 What a blunder!

Vocabulary resource: EdPrep

Facebook page: fb.com/EdPrep


Last edited by cyberjadugar on 14 Jun 2012, 03:40, edited 1 time in total.
Expert Post
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 27493
Followers: 4312

Kudos [?]: 42288 [0], given: 6012

Re: What is the perimeter of isosceles triangle MNP? [#permalink] New post 14 Jun 2012, 03:30
Expert's post
cyberjadugar wrote:
Hi,

Perimeter of isosceles triangle MNP?

Using (1),
MN = 16, no idea about NP & MP. Insufficient.

Using (2)
NP = 20, no idea about MN & MP. Insufficient.

Combining both the statements,
MN = 16 & NP = 20
for MNP to be isosceles, the third side MP can be 16 or 20. Insufficient.

Thus, Answer is (E).

Regards,


Just a bit harder question, based on OG#28:

What is the perimeter of isosceles triangle MNP?

(1) MN = 16
(2) NP = 32

What would be the answer in this case?
_________________

NEW TO MATH FORUM? PLEASE READ THIS: ALL YOU NEED FOR QUANT!!!

PLEASE READ AND FOLLOW: 11 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory; 7. Remainders; 8. Overlapping Sets; 9. PDF of Math Book; 10. Remainders; 11. GMAT Prep Software Analysis NEW!!!; 12. SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) NEW!!!; 12. Tricky questions from previous years. NEW!!!;

COLLECTION OF QUESTIONS:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS ; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
25 extra-hard Quant Tests

GMAT Club Premium Membership - big benefits and savings

1 KUDOS received
Senior Manager
Senior Manager
User avatar
Joined: 28 Mar 2012
Posts: 287
Concentration: Entrepreneurship
GMAT 1: 640 Q50 V26
GMAT 2: 660 Q50 V28
GMAT 3: 730 Q50 V38
Followers: 17

Kudos [?]: 206 [1] , given: 23

GMAT ToolKit User
Re: What is the perimeter of isosceles triangle MNP? [#permalink] New post 14 Jun 2012, 03:38
1
This post received
KUDOS
Bunuel wrote:
cyberjadugar wrote:
Hi,

Perimeter of isosceles triangle MNP?

Using (1),
MN = 16, no idea about NP & MP. Insufficient.

Using (2)
NP = 20, no idea about MN & MP. Insufficient.

Combining both the statements,
MN = 16 & NP = 20
for MNP to be isosceles, the third side MP can be 16 or 20. Insufficient.

Thus, Answer is (E).

Regards,


Just a bit harder question, based on OG#28:

What is the perimeter of isosceles triangle MNP?

(1) MN = 16
(2) NP = 32

What would be the answer in this case?

Hi,

Using (1) & (2) alone we can't get the answer (similar to the explanation above)

Combinig (1) & (2),
MN = 16 & NP = 32
Possible sides of triangle (16, 16, 32) & (16, 32, 32),
now we know a+b>c (sum of two sides greater than third side)
(16, 16, 32) doesn't fulfill this criteria
Thus only possible triangle is (16, 32, 32)
perimeter = 80

Thus, Answer is (C)

Regards,
_________________

My posts: Solving Inequalities, Solving Simultaneous equations, Divisibility Rules

My story: 640 What a blunder!

Vocabulary resource: EdPrep

Facebook page: fb.com/EdPrep

Expert Post
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 27493
Followers: 4312

Kudos [?]: 42288 [0], given: 6012

Re: What is the perimeter of isosceles triangle MNP? [#permalink] New post 14 Jun 2012, 03:46
Expert's post
cyberjadugar wrote:
Bunuel wrote:
cyberjadugar wrote:
Hi,

Perimeter of isosceles triangle MNP?

Using (1),
MN = 16, no idea about NP & MP. Insufficient.

Using (2)
NP = 20, no idea about MN & MP. Insufficient.

Combining both the statements,
MN = 16 & NP = 20
for MNP to be isosceles, the third side MP can be 16 or 20. Insufficient.

Thus, Answer is (E).

Regards,


Just a bit harder question, based on OG#28:

What is the perimeter of isosceles triangle MNP?

(1) MN = 16
(2) NP = 32

What would be the answer in this case?

Hi,

Using (1) & (2) alone we can't get the answer (similar to the explanation above)

Combinig (1) & (2),
MN = 16 & NP = 32
Possible sides of triangle (16, 16, 32) & (16, 32, 32),
now we know a+b>c (sum of two sides greater than third side)
(16, 16, 32) doesn't fulfill this criteria
Thus only possible triangle is (16, 32, 32)
perimeter = 80

Thus, Answer is (C)

Regards,


Correct.

What is the perimeter of isosceles triangle MNP?

(1) MN = 16
(2) NP = 32

MUST KNOW FOR THE GMAT: The length of any side of a triangle must be larger than the positive difference of the other two sides, but smaller than the sum of the other two sides.

When we consider the two statements together we can see that the case of {16, 16, 32} is not possible since the sum of two sides (16 and 16) is not greater then the third side (32), so only the following case is possible: {16, 32, 32}, which gives the perimeter equal to 16+32+32=80.

Answer: C.

For more on Triangles check: math-triangles-87197.html (Theory, Formulas, Tricks, and Tips).

Hope it helps.
_________________

NEW TO MATH FORUM? PLEASE READ THIS: ALL YOU NEED FOR QUANT!!!

PLEASE READ AND FOLLOW: 11 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory; 7. Remainders; 8. Overlapping Sets; 9. PDF of Math Book; 10. Remainders; 11. GMAT Prep Software Analysis NEW!!!; 12. SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) NEW!!!; 12. Tricky questions from previous years. NEW!!!;

COLLECTION OF QUESTIONS:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS ; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
25 extra-hard Quant Tests

GMAT Club Premium Membership - big benefits and savings

Manager
Manager
User avatar
Joined: 07 Sep 2011
Posts: 65
Location: United States
Concentration: Strategy, International Business
GMAT 1: 640 Q39 V38
WE: General Management (Real Estate)
Followers: 4

Kudos [?]: 28 [0], given: 3

Re: What is the perimeter of isosceles triangle MNP? [#permalink] New post 16 Jun 2012, 04:15
Higher then 550 for sure. I think 600.

Unless we know the property "The length of any side of a triangle must be larger than the positive difference of the other two sides, but smaller than the sum of the other two sides", we can not answer the question easily.

Stmt 1: We can know the second side but don't know the length of third side.
Stmt 2: Same logic as given for stmt 1.

Together the third side can be 16 or it can be 20 also.

E
Expert Post
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 27493
Followers: 4312

Kudos [?]: 42288 [0], given: 6012

Re: What is the perimeter of isosceles triangle MNP? [#permalink] New post 22 Jun 2012, 03:02
Expert's post
SOLUTION

What is the perimeter of isosceles triangle MNP?

(1) MN = 16. We only know the length of one side. Not sufficient.
(2) NP = 20. We only know the length of one side. Not sufficient.

(1)+(2) If MN=MP=16 and NP=20 then the perimeter would be 16+16+20=52 but if MN=16 and NP=MP=20 then the perimeter would be 16+20+20=56. Not sufficient.

Answer: E.

Similar question to practice: what-is-the-perimeter-of-isosceles-triangle-mnp-134505.html#p1096591
_________________

NEW TO MATH FORUM? PLEASE READ THIS: ALL YOU NEED FOR QUANT!!!

PLEASE READ AND FOLLOW: 11 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory; 7. Remainders; 8. Overlapping Sets; 9. PDF of Math Book; 10. Remainders; 11. GMAT Prep Software Analysis NEW!!!; 12. SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) NEW!!!; 12. Tricky questions from previous years. NEW!!!;

COLLECTION OF QUESTIONS:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS ; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
25 extra-hard Quant Tests

GMAT Club Premium Membership - big benefits and savings

Director
Director
User avatar
Status: Final Countdown
Joined: 17 Mar 2010
Posts: 564
Location: India
GPA: 3.82
WE: Account Management (Retail Banking)
Followers: 13

Kudos [?]: 169 [0], given: 75

Re: What is the perimeter of isosceles triangle MNP? [#permalink] New post 23 Jul 2012, 06:47
What is the perimeter of isosceles triangle MNP?
PERIMETER=MN+NP+MP
Not given which sides are equal
(1) MN = 16
NP&MP unavailable so insufficient
(2) NP = 20
MN&MP unavailable so insufficient
from (i)&(ii)
Perimeter=MN+NP+MP=16+20+?, we don't know which two sides are equal;insufficient (E)
_________________

" Make more efforts "
Press Kudos if you liked my post

Manager
Manager
User avatar
Joined: 12 Jan 2013
Posts: 249
Followers: 2

Kudos [?]: 33 [0], given: 47

GMAT ToolKit User
Re: What is the perimeter of isosceles triangle MNP? [#permalink] New post 09 Jan 2014, 09:16
Bunuel wrote:
The Official Guide for GMAT® Review, 13th Edition - Quantitative Questions Project

What is the perimeter of isosceles triangle MNP?

(1) MN = 16
(2) NP = 20

Diagnostic Test
Question: 28
Page: 25
Difficulty: 550




Sides of an isosceles triangle: a, a, b.. We don't know if a = 16 or if a = 20, so E
Intern
Intern
avatar
Joined: 13 Sep 2014
Posts: 9
Location: China
Concentration: General Management, Operations
GMAT 1: 680 Q45 V38
Followers: 0

Kudos [?]: 0 [0], given: 8

Re: What is the perimeter of isosceles triangle MNP? [#permalink] New post 12 Dec 2014, 01:34
Bunuel wrote:
What is the perimeter of isosceles triangle MNP?

(1) MN = 16
(2) NP = 20

Diagnostic Test
Question: 28
Page: 25
Difficulty: 550


Hi all,

when reading "What is the perimeter of Isosceles Triangle MNP", how can I be sure that "MNP" stands for the vertices (as it is the case here) and not for the sides?
If M, N and P each were sides, the result to the question in my opinion would change to "C", as M*N and N*P would HAVE to account for 4*4 and 4*5 in this logic as we're dealing with an isosceles and the rule for the sum of two triangle sides doesn't allow any other solution.

How can I identify these variables to be representing vertices instead of sides?


Thanks
Christian
Expert Post
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 27493
Followers: 4312

Kudos [?]: 42288 [0], given: 6012

Re: What is the perimeter of isosceles triangle MNP? [#permalink] New post 12 Dec 2014, 05:45
Expert's post
christian1904 wrote:
Bunuel wrote:
What is the perimeter of isosceles triangle MNP?

(1) MN = 16
(2) NP = 20

Diagnostic Test
Question: 28
Page: 25
Difficulty: 550


Hi all,

when reading "What is the perimeter of Isosceles Triangle MNP", how can I be sure that "MNP" stands for the vertices (as it is the case here) and not for the sides?
If M, N and P each were sides, the result to the question in my opinion would change to "C", as M*N and N*P would HAVE to account for 4*4 and 4*5 in this logic as we're dealing with an isosceles and the rule for the sum of two triangle sides doesn't allow any other solution.

How can I identify these variables to be representing vertices instead of sides?


Thanks
Christian


You are over-thinking this one. Capital letters refer to vertices.
_________________

NEW TO MATH FORUM? PLEASE READ THIS: ALL YOU NEED FOR QUANT!!!

PLEASE READ AND FOLLOW: 11 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory; 7. Remainders; 8. Overlapping Sets; 9. PDF of Math Book; 10. Remainders; 11. GMAT Prep Software Analysis NEW!!!; 12. SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) NEW!!!; 12. Tricky questions from previous years. NEW!!!;

COLLECTION OF QUESTIONS:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS ; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
25 extra-hard Quant Tests

GMAT Club Premium Membership - big benefits and savings

Intern
Intern
avatar
Joined: 28 Jul 2014
Posts: 9
Followers: 0

Kudos [?]: 0 [0], given: 0

Re: What is the perimeter of isosceles triangle MNP? [#permalink] New post 22 Dec 2014, 10:12
Bunuel wrote:
christian1904 wrote:
Bunuel wrote:
What is the perimeter of isosceles triangle MNP?

(1) MN = 16
(2) NP = 20

Diagnostic Test
Question: 28
Page: 25
Difficulty: 550


Hi all,

when reading "What is the perimeter of Isosceles Triangle MNP", how can I be sure that "MNP" stands for the vertices (as it is the case here) and not for the sides?
If M, N and P each were sides, the result to the question in my opinion would change to "C", as M*N and N*P would HAVE to account for 4*4 and 4*5 in this logic as we're dealing with an isosceles and the rule for the sum of two triangle sides doesn't allow any other solution.

How can I identify these variables to be representing vertices instead of sides?


Thanks
Christian


You are over-thinking this one. Capital letters refer to vertices.



Would the angle rules of isosceles triangles not apply here? Since we know sides of 16, 20 - would the remaining side not have to be 16 in order to maintain 1:1:\sqrt{2} ???
Re: What is the perimeter of isosceles triangle MNP?   [#permalink] 22 Dec 2014, 10:12
    Similar topics Author Replies Last post
Similar
Topics:
What is the perimeter of isosceles triangle ABC? AkshayChittoria 0 05 Sep 2013, 21:58
14 Experts publish their posts in the topic In the figure above triangles ABC and MNP are both isosceles rxs0005 8 14 Feb 2012, 06:59
2 What is the perimeter of the isosceles right triangle ABC rxs0005 10 12 Jul 2011, 08:46
1 Experts publish their posts in the topic What is the perimeter of a isosceles triangle MNP? zz0vlb 4 27 Apr 2010, 19:03
5 Experts publish their posts in the topic What is the perimeter of isosceles triangle ABC? GMATT73 5 31 Aug 2006, 23:41
Display posts from previous: Sort by

What is the perimeter of isosceles triangle MNP?

  Question banks Downloads My Bookmarks Reviews Important topics  


GMAT Club MBA Forum Home| About| Privacy Policy| Terms and Conditions| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group and phpBB SEO

Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.