geometry
This topic has expert replies
Source: Beat The GMAT — Problem Solving |
-
shankar.ashwin
- Legendary Member
- Posts: 966
- Joined: Sat Jan 02, 2010 8:06 am
- Thanked: 230 times
- Followed by:21 members
Though not given, we could infer from the figure the 4 triangles are 6-8-10 right triangles. Perimeter would be 6+8+10 = 24
-
GMATGuruNY
- GMAT Instructor
- Posts: 15539
- Joined: Tue May 25, 2010 12:04 pm
- Location: New York, NY
- Thanked: 13060 times
- Followed by:1906 members
- GMAT Score:790
Common sense tells us that the four triangles are congruent right triangles.
Inner square:
Since p=8, s=2 and A = 2² = 4.
Each triangle:
Since the area of the inner square = 4, and the area of the outer square = 100, the area of each triangle = (100-4)/4 = 24.
ALWAYS LOOK FOR SPECIAL TRIANGLES.
Since the hypotenuse of each triangle is 10, it is likely that each triangle is a 6-8-10 triangle.
In a 6-8-10 triangle, A = (1/2)bh = (1/2)(6)(8) = 24. This works.
Thus, p = 6+8+10 = 24.
The correct answer is E.
Private tutor exclusively for the GMAT and GRE, with over 20 years of experience.
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
Student Review #2
Student Review #3
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
Student Review #2
Student Review #3
