It is currently 23 Feb 2018, 10:24

Close

GMAT Club Daily Prep

Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Close

Request Expert Reply

Confirm Cancel

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

An integer n between 1 and 99, inclusive, is to be chosen at

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Intern
Intern
avatar
B
Joined: 05 Nov 2016
Posts: 27
Location: India
Concentration: Operations
GMAT 1: 610 Q48 V26
GMAT 2: 660 Q49 V31
GPA: 3.9
WE: Engineering (Consulting)
An integer n between 1 and 99, inclusive, is to be chosen at [#permalink]

Show Tags

New post 23 Aug 2017, 09:52
Hi Bunuel
I solved the sum using the following approach, but got it wrong. Can you please explain the error in my approach.
For n(n+1) to be divisible by 3, either
a) n must be a multiple of 3 --> Number of possibilities = 96/3 = 32 (because if we consider n=99 then n+1 will not lie between 1 and 99, so the last number that n can be is 96)OR
b) (n +1) must be a multiple of 3 --> Number of possibilities = 99/3 = 33

Now, favorable possibilities = 65 and total possibilities = 99

Therefore, probability = 65/99
An integer n between 1 and 99, inclusive, is to be chosen at   [#permalink] 23 Aug 2017, 09:52
Display posts from previous: Sort by

An integer n between 1 and 99, inclusive, is to be chosen at

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  


GMAT Club MBA Forum Home| About| Terms and Conditions| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne

Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.