GRE Prep 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
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
In the circle above, if the area of the rectangle set inside
[#permalink]
17 Feb 2019, 02:13
17 Feb 2019, 02:13
Expert Reply
00:00
Question Stats:
100% (05:19) correct
0% (00:00) wrong based on 1 sessions
Hide Show timer Statistics
Attachment:
#GREpracticequestion In the circle above, if the area of the rectangle set inside the circle.jpg [ 15.01 KiB | Viewed 1418 times ]
In the circle above, if the area of the rectangle set inside the circle is 200 and b = 8a, what is the circumference of the circle?
A) \(25 \pi \sqrt{65}\)
B) \(5 \sqrt{65}\)
C) \(5 \pi \sqrt{13}\)
D) \(5\pi \sqrt{65}\)
E) \(5 \pi\)
examPAL Representative
Joined: 27 Nov 2018
Posts: 37
Given Kudos: 0
Re: In the circle above, if the area of the rectangle set inside
[#permalink]
18 Feb 2019, 00:30
18 Feb 2019, 00:30
1
The rectangle's diagonal is a diameter, hence angle ab is 90.
this means we can use the Pythagorus theorem: diameter^2 = a^2 + (8a)^2 = a^2+64a^2= 65a^2
diameter = root(65)a
radius = a*root(65)/2
circumference = 2pi*r=2pi*a*root(65)/2 = pi*a*root(65)
now, we also know that The rectangle's are is 200, hence a*b=200 ==> a(8a)=200 ==> 8a^2=200 ==> a^2=25 ==> a= 5
circumference = pi *5 * root65
Answer D
this means we can use the Pythagorus theorem: diameter^2 = a^2 + (8a)^2 = a^2+64a^2= 65a^2
diameter = root(65)a
radius = a*root(65)/2
circumference = 2pi*r=2pi*a*root(65)/2 = pi*a*root(65)
now, we also know that The rectangle's are is 200, hence a*b=200 ==> a(8a)=200 ==> 8a^2=200 ==> a^2=25 ==> a= 5
circumference = pi *5 * root65
Answer D
gmatclubot
Re: In the circle above, if the area of the rectangle set inside [#permalink]
18 Feb 2019, 00:30
Moderators:
