NEW HERE? LEARN MORE
closeclose
Last visit was: 26 Apr 2024, 10:13 It is currently 26 Apr 2024, 10:13
Decision Tracker
My Rewards
New posts
New comers' posts

Close
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
Your Progress

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
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Go to My Error Log Learn more
Close
Request Expert Reply
Confirm Cancel

In the figure above, the vertices of triangle ABC lie on the circumfer

SORT BY:
Date
Kudos
Tags:
Find Similar Topics 
Show Tags
Hide Tags
User avatar
nechets
Manager
Manager
Joined: 04 Oct 2013
Posts: 64
Own Kudos [?]: 292 [2]
Given Kudos: 45
Location: Brazil
Schools: INSEAD Jan '17 (A)
GMAT 1: 660 Q45 V35
GMAT 2: 710 Q49 V38
Send PM
Reviews Badge
In the figure above, the vertices of triangle ABC lie on the circumfer [#permalink] New post   26 Dec 2013, 06:01
2
Bookmarks
00:00
A
B
C
D
E

Difficulty:

15% (low)

Question Stats:

82% (01:10) correct 18% (01:31) wrong based on 169 sessions
Hide Show timer Statistics


In the figure above, the vertices of triangle ABC lie on the circumference of circle O. What is the value of x?

(A) 35
(B) 45
(C) 55
(D) 65
(E) 70


Show Spoiler
I'm puzzled. If one solve for angle AOB, it would imply a different result. Why?
Attachment:
GC_Circles-e1517384956903.png
GC_Circles-e1517384956903.png [ 10.87 KiB | Viewed 1926 times ]
ShowHide Answer
Official Answer
C
User avatar
L
Bunuel
Math Expert
Joined: 02 Sep 2009
Posts: 92946
Own Kudos [?]: 619200 [2]
Given Kudos: 81609
Send PM
CAT Tests Forum Quiz Mode
Re: In the figure above, the vertices of triangle ABC lie on the circumfer [#permalink] New post   26 Dec 2013, 06:20
1
Kudos
1
Bookmarks
Expert Reply
nechets wrote:


In the fi…gure above, the vertices of triangle ABC lie on the circumference of circle O. What is the value of x?

(A) 35
(B) 45
(C) 55
(D) 65
(E) 70


Show Spoiler
I'm puzzled. If one solve for angle AOB, it would imply a different result. Why?


All angels:

Notice that OB = OC = radius, thus triangle OBC is isosceles. Therefore angle OCB = angle OBC --> x + x + 70° = 180° --> x = 55°.

Answer: C.

Hope it's clear.

Show Spoiler
Attachment:
Imagem1.jpg
Imagem1.jpg [ 27.04 KiB | Viewed 3775 times ]
User avatar
L
EgmatQuantExpert
e-GMAT Representative
Joined: 04 Jan 2015
Posts: 3726
Own Kudos [?]: 16844 [0]
Given Kudos: 165
Send PM
Re: In the figure above, the vertices of triangle ABC lie on the circumfer [#permalink] New post   31 Jan 2018, 00:50
Expert Reply
nechets wrote:

In the figure above, the vertices of triangle ABC lie on the circumference of circle O. What is the value of x?

(A) 35
(B) 45
(C) 55
(D) 65
(E) 70


Show Spoiler
I'm puzzled. If one solve for angle AOB, it would imply a different result. Why?


Solution





    • Assuming the O is the center of the circle and AC is the diameter.
      o We can infer that the lines OB = OC = OA = radius of the circle.
    • Let us focus on the triangle OBC, in which OB = OC.
      o Since, it is an isosceles triangle
      o Angle OBC = Angle OCB = x
      o And we know that angle BOC = 70
    • Per our conceptual understanding –
      o Sum of internal angles of a triangle = 180
      o Thus, for triangle OBC, we can write
         70 + x + x = 180
         2x = 110
         x = 55
    • Thus, the correct answer is Option C.

Regards,
Saquib
Quant Expert
e-GMAT
User avatar
L
ScottTargetTestPrep
Target Test Prep Representative
Joined: 14 Oct 2015
Status:Founder & CEO
Affiliations: Target Test Prep
Posts: 18763
Own Kudos [?]: 22056 [0]
Given Kudos: 283
Location: United States (CA)
Send PM
Re: In the figure above, the vertices of triangle ABC lie on the circumfer [#permalink] New post   31 Jan 2018, 16:56
Expert Reply
nechets wrote:


In the figure above, the vertices of triangle ABC lie on the circumference of circle O. What is the value of x?

(A) 35
(B) 45
(C) 55
(D) 65
(E) 70



Since sides OC and OB are radii, side OC = side OB, creating an isosceles triangle, and thus angle OCB = angle OBC = x.

Thus, we have:

2x + 70 = 180

2x = 110

x = 55

Answer: C
User avatar
L
stne
SVP
SVP
Joined: 27 May 2012
Posts: 1680
Own Kudos [?]: 1424 [1]
Given Kudos: 632
Send PM
Re: In the figure above, the vertices of triangle ABC lie on the circumfer [#permalink] New post   24 Oct 2018, 02:22
1
Kudos
nechets wrote:


In the figure above, the vertices of triangle ABC lie on the circumference of circle O. What is the value of x?

(A) 35
(B) 45
(C) 55
(D) 65
(E) 70


Show Spoiler
I'm puzzled. If one solve for angle AOB, it would imply a different result. Why?


Dear Moderator,
The figure of the above question is not visible , hope you will look into this. Thank you.
User avatar
L
Bunuel
Math Expert
Joined: 02 Sep 2009
Posts: 92946
Own Kudos [?]: 619200 [0]
Given Kudos: 81609
Send PM
CAT Tests Forum Quiz Mode
Re: In the figure above, the vertices of triangle ABC lie on the circumfer [#permalink] New post   24 Oct 2018, 03:00
Expert Reply
stne wrote:
nechets wrote:


In the figure above, the vertices of triangle ABC lie on the circumference of circle O. What is the value of x?

(A) 35
(B) 45
(C) 55
(D) 65
(E) 70


Show Spoiler
I'm puzzled. If one solve for angle AOB, it would imply a different result. Why?


Dear Moderator,
The figure of the above question is not visible , hope you will look into this. Thank you.


__________________
Fixed that. Thank you.
GMAT Club Bot
gmatclubot
Re: In the figure above, the vertices of triangle ABC lie on the circumfer [#permalink]
24 Oct 2018, 03:00
Moderators:
Bunuel
Math Expert
92945 posts
yashikaaggarwal
Senior Moderator - Masters Forum
3137 posts

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne
Main navigation
GMAT Resources
Partners
MBA Resources
www.gmac.com|www.mba.com | | GMAT Club Rules | Terms and Conditions