November 17, 2018 November 17, 2018 07:00 AM PST 09:00 AM PST Nov. 17, 7 AM PST. Aiming to score 760+? Attend this FREE session to learn how to Define your GMAT Strategy, Create your Study Plan and Master the Core Skills to excel on the GMAT. November 17, 2018 November 17, 2018 09:00 AM PST 11:00 AM PST Join the Quiz Saturday November 17th, 9 AM PST. The Quiz will last approximately 2 hours. Make sure you are on time or you will be at a disadvantage.
Author 
Message 
TAGS:

Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 50585

When positive integer x is divided by 6, the remainder is 1. Which of
[#permalink]
Show Tags
14 Feb 2016, 02:25
Question Stats:
77% (01:04) correct 23% (00:55) wrong based on 128 sessions
HideShow timer Statistics



SVP
Joined: 26 Mar 2013
Posts: 1878

Re: When positive integer x is divided by 6, the remainder is 1. Which of
[#permalink]
Show Tags
15 Feb 2016, 15:15
Bunuel wrote: When positive integer x is divided by 6, the remainder is 1. Which of the following must be true?
I. x is a prime number II. x is odd III. x is divisible by 7
A. I only B. II only C. III only D. I and II only E. II and III only X=6q+1 Examine II) put q=0,1,2,3....... we have x=1,7,13,...25 so x must be odd Examine III) 14/6 has reminder 2 & 49/7 has reminder 1 so not always true Examine I) X= 7 true but while 2 is prime, it does not give reminder 1 Answer: B



Manager
Status: Build your own dreams,Otherwise some one else will hire you to build there's.
Joined: 30 Apr 2015
Posts: 88
Location: India
Concentration: Finance
GMAT 1: 590 Q45 V26 GMAT 2: 660 Q47 V34
GPA: 3.68

When positive integer x is divided by 6, the remainder is 1. Which of
[#permalink]
Show Tags
15 Feb 2016, 18:19
I would also go with B. X=6q+1 i) if x=7,then remainder is 1. if x=11,then remainder is 5 So,X can or cannot be prime. ii) X=6q(even)+1 i.e. x will always be odd . You can plug in values. iii) X1=6q for 7,it is true that it will be divisible by 7 for 13,it X1 will be a multiple of 6 but is not divisible by 7. Ans:B +1 for Kudos. Ace the GMAT
_________________
"Follow your heart and realize that your dream is a dream for a reason" Dori Roberts



EMPOWERgmat Instructor
Status: GMAT Assassin/CoFounder
Affiliations: EMPOWERgmat
Joined: 19 Dec 2014
Posts: 12857
Location: United States (CA)

Re: When positive integer x is divided by 6, the remainder is 1. Which of
[#permalink]
Show Tags
17 Feb 2016, 21:31
Hi All, When dealing with these types of questions, you MUST restrict your 'examples' to ones that fit the description given in the prompt. Here, we're told that X is a positive integer and that when X is divided by 6, the remainder is 1. We're asked which of the following MUST be true. Using the information in the prompt, we can list out the first several numbers that fit the given description: 1, 7, 13, 19, 25 X CANNOT be any other value between 1 and 25 (for example, it can't be 2 or 11 because neither of those values fit what we were told about X). From here, we can quickly eliminate Roman Numerals: I. X is a prime number. Sometimes X is prime, sometimes X is NOT prime. This is NOT always true. II. X is odd This certainly appears true. III. X is divisible by 7 Sometimes X is divisible by 7, sometimes X is NOT divisible by 7. Final Answer: GMAT assassins aren't born, they're made, Rich
_________________
760+: Learn What GMAT Assassins Do to Score at the Highest Levels Contact Rich at: Rich.C@empowergmat.com
Rich Cohen
CoFounder & GMAT Assassin
Special Offer: Save $75 + GMAT Club Tests Free
Official GMAT Exam Packs + 70 Pt. Improvement Guarantee www.empowergmat.com/
*****Select EMPOWERgmat Courses now include ALL 6 Official GMAC CATs!*****



Current Student
Joined: 25 Jun 2014
Posts: 42
WE: Operations (Computer Software)

Re: When positive integer x is divided by 6, the remainder is 1. Which of
[#permalink]
Show Tags
18 Feb 2016, 07:22
Positive integer x is divided by 6, the remainder is 1. So, the number "X" will be of the form (6y+1). Now, I. x is a prime number: True for No such as 7 (6x1+1), 13 (6x2+1),19 (6x3+1) False for No such as 25 (6x4+1), as 25 is not a prime number (divisible by 5,1,25) II. x is odd True, as all the number of the form (6y+1) will be odd. III. x is divisible by 7 True for No such as 7 (6x1+1) False for No such as 13 (6x2+1),19 (6x3+1), 25 (6x4+1) So, the Answer is B
_________________
Did I Help You..If Yes.. Then Kudos Please..



Board of Directors
Status: QA & VA Forum Moderator
Joined: 11 Jun 2011
Posts: 4209
Location: India
GPA: 3.5
WE: Business Development (Commercial Banking)

Re: When positive integer x is divided by 6, the remainder is 1. Which of
[#permalink]
Show Tags
08 Jul 2018, 11:12
Bunuel wrote: When positive integer x is divided by 6, the remainder is 1. Which of the following must be true?
I. x is a prime number II. x is odd III. x is divisible by 7
A. I only B. II only C. III only D. I and II only E. II and III only I. If x = 25 and it is divided by 6, the remainder is 1, however, x is not a Prime number.II. x = 6q + 1 ; 6q will always be an Even number and when 1 is added to it it will always result in an ODD number.III. Similarly If x = 13 and it is divided by 6, the remainder is 1, however, x is not divisible by 7.Thus, Answer must be (B) II.
_________________
Thanks and Regards
Abhishek....
PLEASE FOLLOW THE RULES FOR POSTING IN QA AND VA FORUM AND USE SEARCH FUNCTION BEFORE POSTING NEW QUESTIONS
How to use Search Function in GMAT Club  Rules for Posting in QA forum  Writing Mathematical Formulas Rules for Posting in VA forum  Request Expert's Reply ( VA Forum Only )




Re: When positive integer x is divided by 6, the remainder is 1. Which of &nbs
[#permalink]
08 Jul 2018, 11:12






