The side of a square has the length of 8. What is the area o

This topic has expert replies
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
The side of a square has the length of 8. What is the area of the region shaded?
A. 48-8Ï€
B. 48-6 π
C. 24+6Ï€
D. 16+8Ï€
E. 64-8Ï€

*An answer will be posted in 2 days.
Attachments
1.png

Master | Next Rank: 500 Posts
Posts: 199
Joined: Sat Apr 26, 2014 10:53 am
Thanked: 16 times
Followed by:4 members
GMAT Score:780

by 800_or_bust » Sun Jun 26, 2016 6:37 pm
Max@Math Revolution wrote:The side of a square has the length of 8. What is the area of the region shaded?
A. 48-8Ï€
B. 48-6 π
C. 24+6Ï€
D. 16+8Ï€
E. 64-8Ï€

*An answer will be posted in 2 days.
I'm assuming both of those are semicircles of diameter equal to 8. Hard to tell from the drawing alone. If so, they should intersect right in the middle of the square, so we can draw a smaller square in the far bottom left corner with sides of 4 (the radii of the circle). This square has area of 16. The remaining circular region (consisting of two quarter-circles of radius 4, or collectively one semi-circle) has area equal to 8Ï€ (Ï€(4^2)/2). The total area of the square is 8x8 = 64. Thus, the area of the shaded region is 48-8Ï€.
800 or bust!

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 » Tue Jun 28, 2016 5:26 pm
The area of a square whose side is 8 - (the area of a square whose side is 4 + the area of the semi-circle whose side is 4) = the area of the region shaded
The correct answer is A.