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

GMATPREP question

Expert replies
Post new topic Post Reply
Subscribe topic
Previous Topic Next Topic
Newbie | Next Rank: 10 Posts
Posts: 4
Joined: Fri Nov 10, 2006 11:20 am
by colors » Sun Dec 24, 2006 10:01 am
Hello, I need help with this question.
Q: In the airthmetic sequence t1, t2, t3....tn...t1=23. tn=tn-1-3 for each n>1. What is the value of n when tn=-4?

a) -1 b)7 c)10 d)14 e)20

Thanks!!
Top
Join the discussion
Source: — Problem Solving |
Senior | Next Rank: 100 Posts
Posts: 41
Joined: Fri Dec 15, 2006 9:23 amFollowed by: 1 member
Location: Greece

by thankont » Mon Dec 25, 2006 12:34 am
t1=23 t2=20 and so on...
and tn=t1+(n-1)*d where diffrence is t2-t1=-3
so we have -4=23-3*(n-1) => 3*(n-1)=27 so n=10
Top
Join the discussion
Junior | Next Rank: 30 Posts
Posts: 29
Joined: Thu Mar 11, 2010 3:23 am
Thanked: 1 times

by Haldiram Bhujiawala » Fri May 21, 2010 8:29 am
IMO10
Top
Join the discussion
User avatar
GMAT Instructor
Posts: 1052
Joined: Fri May 21, 2010 1:30 amFollowed by: 98 members
Thanked: 335 times

by Patrick_GMATFix » Fri May 21, 2010 9:48 am
The Q tells us that each term is 3 less than the previous term, so we can literally list out terms from 23 (the first term) until we get to -4. the correct answer is C.

Because there are only a few terms, it wouldn't take more than 45 seconds to just list terms (23, 20, 17...) until we get to -4.

This is QID 1133

-Patrick
Top
Join the discussion