Last visit was: 30 Apr 2026, 15:43 It is currently 30 Apr 2026, 15:43
Home
Messages
Tests
Schools
Events
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
Back to Forum
Create Topic
555-605 (Medium)|   Geometry|      
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 30 Apr 2026
Posts: 110,017
Own Kudos:
812,157
 [6]
Given Kudos: 105,962
Products:
GMAT Club Tests Forum Quiz
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 110,017
Kudos: 812,157
 [6]
In the polygon inscribed in circle O above, ∠A=90°. If AB=AE and BC=CD 15 Jun 2021, 01:30
Kudos
Add Kudos
6
Bookmarks
Bookmark this Post
00:00
Start Timer
Pause Timer
Resume Timer
Show Answer
Hide
Show
History
B
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!

Difficulty:

35% (medium)

Question Stats:

74% (02:38) correct 26% (02:04) wrong based on 43 sessions

History

Date
Time
Result
Not Attempted Yet

In the polygon inscribed in circle O above, ∠A=90°. If AB=AE and BC=CD=DE, as shown above, what is the value of x?

A. 100
B. 105
C. 115
D. 120
E. 150



Project PS Butler


Subscribe to get Daily Email - Click Here | Subscribe via RSS - RSS

Show Spoiler
Attachment:
1.png
1.png [ 9.84 KiB | Viewed 2174 times ]
ShowHide Answer
Official Answer
B
User avatar
sumitkrocks
User avatar
Joined: 02 Jul 2017
Last visit: 22 Aug 2023
Posts: 637
Own Kudos:
879
 [1]
Given Kudos: 333
Location: India
Concentration: Strategy, Technology
Schools: IIMA PGPX'22 ISB'22 NUS '23 ESADE IESE '24 NTU
GMAT 1: 730 Q50 V39
GMAT 2: 710 Q50 V36
Products:
My Reviews
Schools: IIMA PGPX'22 ISB'22 NUS '23 ESADE IESE '24 NTU
GMAT 2: 710 Q50 V36
Posts: 637
Kudos: 879
 [1]
In the polygon inscribed in circle O above, ∠A=90°. If AB=AE and BC=CD 15 Jun 2021, 03:30
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
EB is the diameter of the circle with center O (Say)
Angle AEO and Angle ABO will be 45degrees each
Joining EO, DO and CO will give three Equilateral triangles {Measure of arc= Measure of central angle by the arc = half of inscribed angle}

Angle x = Angle ABO + Angle OBC = 45 + 60 = 105 Degrees

Option (B) is the correct choice IMO

Bunuel

In the polygon inscribed in circle O above, ∠A=90°. If AB=AE and BC=CD=DE, as shown above, what is the value of x?

A. 100
B. 105
C. 115
D. 120
E. 150



Project PS Butler


Subscribe to get Daily Email - Click Here | Subscribe via RSS - RSS

Show Spoiler
Attachment:
1.png
Show more
avatar
KetakiUpadhye
avatar
Joined: 26 Sep 2020
Last visit: 29 Mar 2023
Posts: 12
Given Kudos: 75
Posts: 12
Kudos: 0
In the polygon inscribed in circle O above, ∠A=90°. If AB=AE and BC=CD 20 Jun 2021, 18:11
Kudos
Add Kudos
Bookmarks
Bookmark this Post
sumitkrocks
EB is the diameter of the circle with center O (Say)
Angle AEO and Angle ABO will be 45degrees each
Joining EO, DO and CO will give three Equilateral triangles {Measure of arc= Measure of central angle by the arc = half of inscribed angle}

Angle x = Angle ABO + Angle OBC = 45 + 60 = 105 Degrees

Option (B) is the correct choice IMO

Bunuel

In the polygon inscribed in circle O above, ∠A=90°. If AB=AE and BC=CD=DE, as shown above, what is the value of x?

A. 100
B. 105
C. 115
D. 120
E. 150



Project PS Butler


Subscribe to get Daily Email - Click Here | Subscribe via RSS - RSS

Show Spoiler
Attachment:
1.png
Show more

Hi Sumit can you please explain the part of the equilateral triangle again. Thanks

Posted from my mobile device
User avatar
Shahalikhan
User avatar
Joined: 08 Jul 2019
Last visit: 08 May 2023
Posts: 59
Own Kudos:
125
 [1]
Given Kudos: 1,121
Location: United Kingdom
Concentration: Strategy, General Management
Schools: Anderson '24 Booth '24 CEIBS '24 Columbia CBS '24 Goizueta '24 ESADE Foster '24 Fuqua '24 Haas '24 Harvard '24 HKUST IESE '24 IMD '22 ISB '23 Johnson '24 Judge '23 Kellogg '24 Kenan-Flagler '24 LBS '24 McCombs '24 McDonough '24 NTU NUS Said '23 Ross '24 Rotman '24 Erasmus Bocconi Sloan '24 Stanford '24 Tepper '24 Tuck '24 Warwick "23 Wharton '24 Yale '24
GMAT 1: 710 Q50 V37
GPA: 3.51
WE:General Management (Computer Software)
Schools: Anderson '24 Booth '24 CEIBS '24 Columbia CBS '24 Goizueta '24 ESADE Foster '24 Fuqua '24 Haas '24 Harvard '24 HKUST IESE '24 IMD '22 ISB '23 Johnson '24 Judge '23 Kellogg '24 Kenan-Flagler '24 LBS '24 McCombs '24 McDonough '24 NTU NUS Said '23 Ross '24 Rotman '24 Erasmus Bocconi Sloan '24 Stanford '24 Tepper '24 Tuck '24 Warwick "23 Wharton '24 Yale '24
GMAT 1: 710 Q50 V37
Posts: 59
Kudos: 125
 [1]
In the polygon inscribed in circle O above, ∠A=90°. If AB=AE and BC=CD 20 Jun 2021, 19:01
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
KetakiUpadhye
sumitkrocks
EB is the diameter of the circle with center O (Say)
Angle AEO and Angle ABO will be 45degrees each
Joining EO, DO and CO will give three Equilateral triangles {Measure of arc= Measure of central angle by the arc = half of inscribed angle}

Angle x = Angle ABO + Angle OBC = 45 + 60 = 105 Degrees

Option (B) is the correct choice IMO

Bunuel

In the polygon inscribed in circle O above, ∠A=90°. If AB=AE and BC=CD=DE, as shown above, what is the value of x?

A. 100
B. 105
C. 115
D. 120
E. 150



Project PS Butler


Subscribe to get Daily Email - Click Here | Subscribe via RSS - RSS

Show Spoiler
Attachment:
1.png

Hi Sumit can you please explain the part of the equilateral triangle again. Thanks

Posted from my mobile device
Show more




Hi
the basic principle of a circle

equal chords subtend equal angles at the center, No matter their relative position with the center of the circle


SO angle subtended by DE,DC & CB at center are same and their total equals 180 degree so each of them equals 60 degree

give kudos
Moderators:
Bunuel
Math Expert
110017 posts
Krunaal
Tuck School Moderator
852 posts