BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

ABCD is a square with AB=10. What is the perimeter of the sh

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
User avatar
Elite Legendary Member
Posts: 3991
Joined: Fri Jul 24, 2015 2:28 am
Location: Las Vegas, USA
Thanked: 19 times
Followed by:37 members

ABCD is a square with AB=10. What is the perimeter of the sh

by Max@Math Revolution » Thu Jul 25, 2019 12:13 am
[GMAT math practice question]

ABCD is a square with AB=10. What is the perimeter of the shaded area?

Image

A. 10Ï€/3 +10
B. 5Ï€/3 +10
C. 5Ï€/6 +10
D. 5Ï€/3 +5
E. 5Ï€/6 +5
Top
Source: — Problem Solving |
User avatar
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

by GMATGuruNY » Thu Jul 25, 2019 2:22 am
The prompt should indicate that ABC and BCD are quarter-circles.
Max@Math Revolution wrote:[GMAT math practice question]

ABCD is a square with AB=10. What is the perimeter of the shaded area?

Image

A. 10Ï€/3 +10
B. 5Ï€/3 +10
C. 5Ï€/6 +10
D. 5Ï€/3 +5
E. 5Ï€/6 +5
Perimeter of shaded region = AD + (AP+DP) = 10 + (more than 10)
Only A is viable:
(10Ï€)/3 + 10 = more than 10 + 10

The correct answer is A.
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
Top
User avatar
Elite Legendary Member
Posts: 3991
Joined: Fri Jul 24, 2015 2:28 am
Location: Las Vegas, USA
Thanked: 19 times
Followed by:37 members

by Max@Math Revolution » Sun Jul 28, 2019 4:56 pm
=>

Image

Since triangle PBC is equilateral, angle ABP has measure 30° and the length of arc AP is 2π*10*(30/360) = (5/3) π.
Thus, the perimeter of the shaded area is (5/3) π *2 + 10 = (10/3) π + 10.


Therefore, A is the answer.
Answer: A
Top
Post new topic Post Reply
• Page 1 of 1