Last visit was: 01 May 2026, 15:51 It is currently 01 May 2026, 15:51
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.
Close
Request Expert Reply
Confirm Cancel
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 01 May 2026
Posts: 110,001
Own Kudos:
Given Kudos: 105,976
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 110,001
Kudos: 812,335
 [28]
1
Kudos
Add Kudos
27
Bookmarks
Bookmark this Post
Most Helpful Reply
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 01 May 2026
Posts: 110,001
Own Kudos:
812,335
 [1]
Given Kudos: 105,976
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 110,001
Kudos: 812,335
 [1]
Kudos
Add Kudos
1
Bookmarks
Bookmark this Post
General Discussion
User avatar
Kinshook
User avatar
Major Poster
Joined: 03 Jun 2019
Last visit: 01 May 2026
Posts: 5,991
Own Kudos:
5,865
 [2]
Given Kudos: 163
Location: India
GMAT 1: 690 Q50 V34
WE:Engineering (Transportation)
Products:
GMAT 1: 690 Q50 V34
Posts: 5,991
Kudos: 5,865
 [2]
2
Kudos
Add Kudos
Bookmarks
Bookmark this Post
User avatar
mSKR
Joined: 14 Aug 2019
Last visit: 10 Mar 2024
Posts: 1,210
Own Kudos:
961
 [1]
Given Kudos: 381
Location: Hong Kong
Concentration: Strategy, Marketing
GMAT 1: 650 Q49 V29
GPA: 3.81
GMAT 1: 650 Q49 V29
Posts: 1,210
Kudos: 961
 [1]
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
if the degree measure of an inscribed angle subtending the red arc is 100° = angle at center
and the degree measure of an inscribed angle subtending the blue arc is 210 = angle at centre

y+ 105+50= 180
y= 25


180-x+50+105= 180
x= 155


x-y= 130

hence b
Attachments

circle.png
circle.png [ 352.19 KiB | Viewed 4718 times ]

User avatar
EatMyDosa
Joined: 06 Jan 2017
Last visit: 01 Dec 2022
Posts: 81
Own Kudos:
114
 [1]
Given Kudos: 283
Location: India
Concentration: General Management, Finance
GPA: 3.33
Products:
Posts: 81
Kudos: 114
 [1]
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Refer to the attached diagram (screenshot)

Given

1. Subtended angle by Arc (Red) = 100 degrees
2. Subtended angle by Arc (Blue) = 210 degrees

We know that

Angle subtended by an arc at the centre of a circle = 2 * (Angle subtended by the same arc at some other

point on the circumference)


Using this property,

(1) In triangle BPD,

Angle (PBD) = 1/2 * Angle (COD)

= 1/2 * 210

Angle (PBD) = 105 degrees

Now, since an arc subtends equal angle in the same segment of a circle, therefore

Angle (PAC) = Angle (PBD) = 105 degrees


(2) In triangle APC,

Angle (PCA) = 1/2 * Angle (AOB)

= 1/2 * 100

Angle (PCA) = 50 degrees


Now, since an arc subtends equal angle in the same segment of a circle, therefore

Angle (PDB)
= Angle (PCA) = 50 degrees

(3) In triangles BPD,

y + 105 + 50 = 180

y = 25 degrees

Now, on a straight-line BC,

x + y = 180, so

x = 180 -y

x = 180 -25

x = 155 degrees


Therefore,

x – y = 155 – 25

x – y = 130 degrees

Option B (correct)

Posted from my mobile device
Attachments

IMG_20200905_190841.JPG
IMG_20200905_190841.JPG [ 2.36 MiB | Viewed 3831 times ]

User avatar
bumpbot
User avatar
Non-Human User
Joined: 09 Sep 2013
Last visit: 04 Jan 2021
Posts: 39,014
Own Kudos:
Posts: 39,014
Kudos: 1,122
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Automated notice from GMAT Club BumpBot:

A member just gave Kudos to this thread, showing it’s still useful. I’ve bumped it to the top so more people can benefit. Feel free to add your own questions or solutions.

This post was generated automatically.
Moderators:
Math Expert
110001 posts
Tuck School Moderator
852 posts