• 5-Day Free Trial
5-day free, full-access trial TTP Quant

Available with Beat the GMAT members only code

• Free Veritas GMAT Class
Experience Lesson 1 Live Free

Available with Beat the GMAT members only code

• Free Practice Test & Review
How would you score if you took the GMAT

Available with Beat the GMAT members only code

• 5 Day FREE Trial
Study Smarter, Not Harder

Available with Beat the GMAT members only code

• Free Trial & Practice Exam
BEAT THE GMAT EXCLUSIVE

Available with Beat the GMAT members only code

• Award-winning private GMAT tutoring
Register now and save up to $200 Available with Beat the GMAT members only code • Most awarded test prep in the world Now free for 30 days Available with Beat the GMAT members only code • 1 Hour Free BEAT THE GMAT EXCLUSIVE Available with Beat the GMAT members only code • Magoosh Study with Magoosh GMAT prep Available with Beat the GMAT members only code • Get 300+ Practice Questions 25 Video lessons and 6 Webinars for FREE Available with Beat the GMAT members only code Triangles in a heptagon This topic has 1 expert reply and 1 member reply rahulvsd Master | Next Rank: 500 Posts Joined 07 Sep 2010 Posted: 184 messages Followed by: 1 members Upvotes: 6 Triangles in a heptagon Mon Mar 05, 2012 6:46 am How many triangles can be inscribed in the heptagon pictured, where the three vertices of the triangle are also vertices of the heptagon? A.9 B. 21 C. 35 D. 140 E. 210. Ans: C. Grockit solves this by using combinations method and I agree with this solution. If the question mentions non-overlapping triangle, will the answer be 5. By using formula (n-2) *180, so here it will be 5 * 180 so 5 triangles, is this approach correct? And if the question was rephrased as number of triangles (does not mention non - overlapping) in a hexagon by the combination method answer will be 6 factorial / 3 factorial * 3 factorial. So 20 triangles, is this correct too? please confirm... GMAT/MBA Expert Jim@StratusPrep MBA Admissions Consultant Joined 11 Nov 2011 Posted: 2278 messages Followed by: 265 members Upvotes: 660 GMAT Score: 770 Mon Mar 05, 2012 11:14 am 35 is the answer: 7*6*5/3! _________________ GMAT Answers provides a world class adaptive learning platform. -- Push button course navigation to simplify planning -- Daily assignments to fit your exam timeline -- Organized review that is tailored based on your abiility -- 1,000s of unique GMAT questions -- 100s of handwritten 'digital flip books' for OG questions -- 100% Free Trial and less than$20 per month after.
-- Free GMAT Quantitative Review

pemdas Legendary Member
Joined
15 Apr 2011
Posted:
1085 messages
Followed by:
21 members
158
Mon Mar 05, 2012 10:58 am
i selected this option --> one vertice needs two more vertices to form triangle and in total three vertices will be required out of seven, 7C3=35

c

_________________
Success doesn't come overnight!

Best Conversation Starters

1 lheiannie07 108 topics
2 ardz24 67 topics
3 Roland2rule 63 topics
4 LUANDATO 52 topics
5 Vincen 51 topics
See More Top Beat The GMAT Members...

Most Active Experts

1 GMATGuruNY

The Princeton Review Teacher

150 posts
2 Jeff@TargetTestPrep

Target Test Prep

114 posts
3 Rich.C@EMPOWERgma...

EMPOWERgmat

105 posts
4 Scott@TargetTestPrep

Target Test Prep

101 posts
5 Max@Math Revolution

Math Revolution

85 posts
See More Top Beat The GMAT Experts