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
Start free 5-day trial
Read 563 reviewsTarget Test Prep

29-17

Expert replies
Post new topic Post Reply
Subscribe topic
Previous Topic Next Topic
Master | Next Rank: 500 Posts
Posts: 484
Joined: Sun Jul 30, 2006 7:01 pmFollowed by: 1 member
Thanked: 2 times
by magical cook » Tue Aug 28, 2007 11:16 am
Can you pls help with your explanation? thanks!
You do not have the required permissions to view the files attached to this post.
Top
Join the discussion
Source: — Problem Solving |
Senior | Next Rank: 100 Posts
Posts: 98
Joined: Mon Jun 11, 2007 10:32 pm
Location: Mumbai

by ratindasgupta » Tue Aug 28, 2007 1:05 pm
There are two ways you can solve this question

One is the dependant probability format.
If two non defective pens have to be selected, the probability of selecting first one is 9/12 and the probability of selecting the second one is 8/11.

9/12 x 8/11 = 6/11

The second method is using the hypergeometric probability formula which is (number of favourable events)/(total number of events).

number of favourable events = 9C2
total number of events = 12C2

9C2/12C2 = 6/11
Top
Join the discussion
Master | Next Rank: 500 Posts
Posts: 484
Joined: Sun Jul 30, 2006 7:01 pmFollowed by: 1 member
Thanked: 2 times

by magical cook » Tue Aug 28, 2007 2:42 pm
yes OA is 6/11. thanks.
Top
Join the discussion
Senior | Next Rank: 100 Posts
Posts: 47
Joined: Tue Aug 14, 2007 2:36 pm

by crackitpal » Wed Aug 29, 2007 11:05 am
is this question from PS practice questions available from this site ?
Top
Join the discussion