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 →

arith issue

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
Source: — Problem Solving |
User avatar
Master | Next Rank: 500 Posts
Posts: 392
Joined: Sun May 16, 2010 2:42 amFollowed by: 10 members
Location: Bangalore, India
Thanked: 116 times
GMAT Score:770

by albatross86 » Wed Jun 16, 2010 8:11 am
The ones that have a remainder of 2 will all be 1 less than the multiples of 3. (Example 102-1 = 101 , 999-1 = 998)

So we have an arithmetic progression: first term = 101, last term = 998. Difference between 2 terms = 3

a(n) = a(1) + (n-1) * d
=> 998 = 101 + (n-1) * 3
=> n = 300

Sn = n/2(a1 + an) = 300/2 * (101+998) = 150 * 1099 ... Ans
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
User avatar
Legendary Member
Posts: 1893
Joined: Sun May 30, 2010 11:48 pmFollowed by: 7 members
Thanked: 215 times

by kvcpk » Wed Jun 16, 2010 8:14 am
This is just an arithmetic sequence.

first such number is 101. last number is 998.
101, 104,................995,998

sum = n/2(2a+(n-1)*d)
n will be same as number of multiples of 3 between 100 and 1000.

for 1000 there are 333 and for 100 there are 33. so n for us is 300

sum = 300/2(202+(299)*3) = 164850

Please Let me know OA
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
User avatar
Master | Next Rank: 500 Posts
Posts: 294
Joined: Wed May 05, 2010 4:01 am
Location: india
Thanked: 57 times

by amising6 » Wed Jun 16, 2010 8:15 am
What is the sum of all 3 digit numbers that leave a remainder of '2' when divided by 3?

is there technique to resolve quickly please?

soln: basically we want number of the form 3k+2

1st 3 digit number will be 100/3=33 so for k=33 you will get 101 as first number now it will be AP series with 3 as common difference3
last number will be 999/3=333 for k =333 you will get 4 digit number i.e 333*3 + 2=1001
so last 3 digit number will be for k=332 and number will be 333*3+2=998

so all together k will take 332-33+1=300 values
so sum [= n/2*(a+l) ap formula
150(101+998)=150(1099)=29850


in short number will be of form 3k+2
first number=101 last number 998
then arithmetic progression sum formula
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
User avatar
Master | Next Rank: 500 Posts
Posts: 294
Joined: Wed May 05, 2010 4:01 am
Location: india
Thanked: 57 times

by amising6 » Wed Jun 16, 2010 8:16 am
typo error answer will be 164850
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Master | Next Rank: 500 Posts
Posts: 124
Joined: Sun Mar 07, 2010 3:15 pm
Thanked: 1 times

by francoisph » Wed Jun 16, 2010 8:29 am
thks guys

have you maths background?
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
User avatar
Master | Next Rank: 500 Posts
Posts: 294
Joined: Wed May 05, 2010 4:01 am
Location: india
Thanked: 57 times

by amising6 » Wed Jun 16, 2010 8:31 am
not exactly but i like numbers
specially number properties
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Master | Next Rank: 500 Posts
Posts: 124
Joined: Sun Mar 07, 2010 3:15 pm
Thanked: 1 times

by francoisph » Wed Jun 16, 2010 8:52 am
gmat is nightmare whether you are not good in numbers or fast !

I did my ba in economics in 2001, so long time ago o:)
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1