Find all School-related info fast with the new School-Specific MBA Forum

 It is currently 26 Apr 2015, 13:10

GMAT 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

we will pick new questions that match your level based on your Timer History

Track

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

An equilateral triangle is inscribed in circle. The length

Author Message
TAGS:
Intern
Joined: 18 Dec 2007
Posts: 4
Followers: 0

Kudos [?]: 3 [2] , given: 0

An equilateral triangle is inscribed in circle. The length [#permalink]  30 Jan 2008, 23:13
2
KUDOS
An equilateral triangle is inscribed in circle. The length of the arc is 24, what is the radius of the circle.

I came across the above questions, but do not have answer options. Can someone tell me how to solve above problem?
SVP
Joined: 04 May 2006
Posts: 1936
Schools: CBS, Kellogg
Followers: 19

Kudos [?]: 433 [2] , given: 1

2
KUDOS
chandra23 wrote:
An equilateral triangle is inscribed in circle. The length of the arc is 24, what is the radius of the circle.

I came across the above questions, but do not have answer options. Can someone tell me how to solve above problem?

2*pi*r = 3*24
r=36/pi
_________________
Manager
Joined: 18 May 2007
Posts: 56
Followers: 1

Kudos [?]: 18 [2] , given: 0

2
KUDOS
Manager
Joined: 11 Dec 2007
Posts: 121
Followers: 1

Kudos [?]: 5 [2] , given: 0

2
KUDOS
set up an equation:

because it is an eq tri, you know that all angles are equal, thus 24 represents 1/3 of the circ. (using angles 120/360)

so: 1/3=24/circ
circ = 72
solve for d= 72/pi
solve for r=36/pi
Intern
Joined: 03 Mar 2007
Posts: 31
Followers: 0

Kudos [?]: 6 [2] , given: 0

2
KUDOS
As long as you know the formula for the circumference of a circle this problem should be very easy

2 * pi * r = circumference

Always use a diagram

Since you have an equilateral triangle within a circle you know that one arc (24) equals 1/3 of the entire circumference

so 2 * pi * r = 3 * 24
2 * pi * r = 72
pi * r = 36
r = 36 / pi
CEO
Joined: 29 Mar 2007
Posts: 2591
Followers: 16

Kudos [?]: 234 [1] , given: 0

1
KUDOS
chandra23 wrote:
An equilateral triangle is inscribed in circle. The length of the arc is 24, what is the radius of the circle.

I came across the above questions, but do not have answer options. Can someone tell me how to solve above problem?

Which arc? I don't know how you are coming up with answers here. The arc could be 1 side of the traingle or 2 sides.

1 case leaves you a radius of 36/pi, the other 18/pi.
Similar topics Replies Last post
Similar
Topics:
2 An equilateral triangle is inscribed in a circle. If the 4 11 Apr 2012, 06:58
1 164 Equilateral triangle is inscribed in a circle. If length 4 05 Mar 2011, 07:50
A circle is inscribed in equilateral triangle ABC such that 6 01 Oct 2006, 10:43
A circle inscribed in an equilateral triangle with side 4 20 Aug 2006, 01:07
A circle inscribed in an equilateral triangle with side 4 31 Dec 2005, 22:18
Display posts from previous: Sort by