BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem
TTP OnDemand GMAT Video Course
Featured Course

Target Test Prep GMAT OnDemand

Scott Woodbury-Stewart’s private virtual classroom — 400 hours of master-class video lessons for the GMAT Focus Edition.

  • 715+ score guarantee — highest in the industry (99th percentile)
  • 52 chapters · 1,500+ lessons · 4,000+ practice questions
  • 400 hours of video · 1,500+ instructor-led HD smartboard lessons
  • 300,000+ students accepted to Harvard, Stanford, Wharton, Booth & Sloan & more
  • 24/7 live support + weekly Zoom office hours with GMAT instructors
  • TTP AI Assist — 24/7 AI-powered virtual tutor for instant help
  • 1,200+ flashcards + AI-powered study assistant & daily calendar
  • OnDemand, LiveTeach & GMAT Bootcamp formats available
  • Also: GRE, SAT Math & Executive Assessment courses
  • MBA Admissions Consulting now available
  • 🏆 2025 EdTech Breakthrough Award: Test Prep Solution Provider of the Year
  • 200,000+ students served
  • 5-day free trial — $0 to start, no auto-billing, cancel anytime
★★★★★ 5.0 (559 reviews)
130-pt guarantee
$0 to start then $127/mo
Start Free 5-Day Trial Read 559 Reviews →

A sequence An is there such that An=An-1-An-2 where n are in

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
Master | Next Rank: 500 Posts
Posts: 157
Joined: Sat Nov 19, 2016 5:34 amFollowed by: 4 members
Thanked: 2 times
by hazelnut01 » Wed May 03, 2017 11:17 pm
A sequence An is there such that An=An-1-An-2 where n are integers greater than 2. What is the value of A5?

(1) A4-A3=3
(2) A14=1

Source : Math Revolution
OA=D
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Data Sufficiency |

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 3008
Joined: Mon Aug 22, 2016 6:19 amFollowed by: 34 members
Location: Grand Central / New York
Thanked: 470 times

by Jay@ManhattanReview » Thu May 04, 2017 12:34 am
ziyuenlau wrote:A sequence An is there such that An=An-1-An-2 where n are integers greater than 2. What is the value of A5?

(1) A4-A3=3
(2) A14=1

Source : Math Revolution
OA=D
We have An=An-1-An-2

Statement 1: A4-A3=3

As per the given relationship, A5 = A4 - A3

=> A5 = 3. Sufficient.

Statement 2: A14=1

A14 = A13 - A12 = A12 - A11- A12 = - A11 = -A10 + A9 = -A9+A8+A9 = A8 = A7-A6 = A6-A5-A6 = -A5

=> A5 = -A14 = -1. Sufficient.

Though each statement is sufficient by itself, the answers from each are not the same.

Either A5 = 3 or A5 = -1. It cannot be both. It seems that one of the statement is incorrectly typed.

The correct answer: D

Hope this helps!

Relevant book: Manhattan Review GMAT Number Properties Guide

-Jay
_________________
Manhattan Review GMAT Prep

Locations: New York | Barcelona | Manila | Melbourne | and many more...

Schedule your free consultation with an experienced GMAT Prep Advisor! Click here.
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1