Live GMAT classes with Target Test Prep start Nov 21 and Nov 22. First class free.

See classes
Target Test Prep · GMAT

Choose how you want to prepare

Learn live with an expert or move at your own pace. Every option includes the complete TTP study system.

Newsweek Readers’ Choice Awards 2026 winner: Target Test Prep, #1 Test Prep

Target Test Prep was voted #1 Best Test Prep in the 2026 Newsweek Readers’ Choice™ Awards.

★★★★★5.0563 reviews
GMATLiveTeachStarts Nov 22
Josh Braslow, Target Test Prep GMAT expert
LIVE ONLINE CLASSES

Get Ready for GMAT Test Day Faster with Live Online Classes

with Josh Braslow, 20+ years in test prep

Nov 22 · Josh Braslow
Sun · 9:30 AM to 12:30 PM ET
Included
40 hours of live online classes + 6 months of TTP OnDemand
  • Attend the first class for free
  • Every class is recorded, so you never fall behind
View classes & enroll
Limited seats availableTarget Test Prep
EALiveTeachOnDemandStart anytime
EXECUTIVE ASSESSMENT

Target Test Prep EA OnDemand

Self-paced EA prep. Study on your schedule.

EXECUTIVE ASSESSMENT

with

165+ EA score guarantee
$05-day trial no automatic billing
Schedule
Included
40 hours of live online classes plus six months of access to the complete TTP EA OnDemand course.
  • 165+ EA Score Guarantee
  • 4,100+ Quant, Verbal, and Integrated Reasoning practice questions
  • 400+ hours of in-depth video lessons
  • 3,000+ step-by-step video solutions
View EA class & enroll Start free 5-day trial
Limited cohort · enrollment openTrial includes full course accessTarget Test Prep
GMATOnDemandStart anytime
SELF-PACED MASTERCLASS

Target Test Prep GMAT OnDemand

Complete access from day one. Study on your schedule.

715+ score guarantee
$0to start then $127/mo
  • Personalized study plan and analytics
  • Thousands of lessons and practice questions

Geometry: Dont take it for granted

Expert replies
by shovan85 » Sun Oct 10, 2010 7:06 am
Explanations Please. OA A
You do not have the required permissions to view the files attached to this post.
Last edited by shovan85 on Sun Oct 10, 2010 8:24 am, edited 1 time in total.
Join the discussion
Source: — Problem Solving |

by thephoenix » Sun Oct 10, 2010 7:12 am
it has been posted no.f times search u will get a link
Many of the great achievements of the world were accomplished by tired and discouraged men who kept on working
Join the discussion

by shovan85 » Sun Oct 10, 2010 7:16 am
thephoenix wrote:it has been posted no.f times search u will get a link
thanks I got it but still worth a post ... as people can get involved in an active discussion :)
Join the discussion

by rohit_gmat » Sun Oct 10, 2010 7:46 am
shovan85 wrote:Explanations Please.
IMO A

r = 18/2 = 9
total upper half = 1/2 x 2 x pi x r = 9 pi

Arc OP = 2 x (35/360) x 2 x pi x 9 = 7/2 pi
And its opposite arc shud be the same since the lines are parallel, so we have :
9 pi - 2(7/2 pi) = 2 pi


Is that correct?
Join the discussion

by shovan85 » Sun Oct 10, 2010 8:23 am
rohit_gmat wrote:
shovan85 wrote:Explanations Please.
IMO A

r = 18/2 = 9
total upper half = 1/2 x 2 x pi x r = 9 pi

Arc OP = 2 x (35/360) x 2 x pi x 9 = 7/2 pi
And its opposite arc shud be the same since the lines are parallel, so we have :
9 pi - 2(7/2 pi) = 2 pi


Is that correct?
Great... the most concise answer ever :)
Join the discussion

by lokesh r » Sun Oct 10, 2010 11:55 pm
rohit_gmat wrote:
shovan85 wrote:Explanations Please.
IMO A

r = 18/2 = 9
total upper half = 1/2 x 2 x pi x r = 9 pi

Arc OP = 2 x (35/360) x 2 x pi x 9 = 7/2 pi
And its opposite arc shud be the same since the lines are parallel, so we have :
9 pi - 2(7/2 pi) = 2 pi


Is that correct?
Arc OP = 2 x (35/360) x 2 x pi x 9 = 7/2 pi
Would be helpful if anycone can explain why is it multiplied by 2 in getting length of arc OP.
Join the discussion

by pharmxanthan » Mon Oct 11, 2010 12:10 am
Because the angle subtended by the chord at the center is double that at the circumference.
Join the discussion

by lokesh r » Mon Oct 11, 2010 3:39 am
pharmxanthan wrote:Because the angle subtended by the chord at the center is double that at the circumference.
Say in the figure attached we call center of the circle as A.

Do you mean angle PAO= 2 x angle PRO
Join the discussion

by fskilnik@GMATH » Mon Oct 11, 2010 7:22 am
Another approach:

01. Angle ORP (35 degrees) is inscribed, therefore (minor) arc OP measures 70 degrees.

02. Angle RPQ measures 35 degrees (parallelism), therefore (minor) arc QR measures 70 degrees.

03. From the fact that arc OPQR measures 180 degrees, (minor) arc PQ measures 40 degrees.

Finally, (minor) arc PQ measures 40/360 = 1/9 of 2*pi*(r=9) , then answer is surely 2pi (choice A)
Fabio Skilnik :: GMATH method creator ( Math for the GMAT)
English-speakers :: https://www.gmath.net
Portuguese-speakers :: https://www.gmath.com.br
Join the discussion

by pharmxanthan » Mon Oct 11, 2010 4:06 pm
lokesh r wrote:
pharmxanthan wrote:Because the angle subtended by the chord at the center is double that at the circumference.
Say in the figure attached we call center of the circle as A.

Do you mean angle PAO= 2 x angle PRO
Yes.
Join the discussion