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

Redeem

silly ques

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Legendary Member
Posts: 833
Joined: Mon Aug 04, 2008 1:56 am
Thanked: 13 times

silly ques

by vivek.kapoor83 » Tue Nov 18, 2008 11:28 am
If y ≠ 3 and 3x/y is a prime integer greater than 2, which of the following must be true?
Ⅰ. x = y
Ⅱ. y = 1
Ⅲ. x and y are prime integers.
(A) None
(B) Ⅰ only
(C) Ⅱonly
(D) Ⅲonly
(E) Ⅰand Ⅲ


I chose B. means if x=y , then expression would result in 3 always.So, I went for option B but OA is diff. I dont know where i am going wrong.
Top
Source: — Problem Solving |
Legendary Member
Posts: 683
Joined: Tue Jul 22, 2008 1:58 pm
Location: Dubai
Thanked: 73 times
Followed by:2 members

by mals24 » Tue Nov 18, 2008 11:42 am
Answer should be A

3x/y is prime integer

let x = 15 y = 9

3*15/9 = 5

Here x is not equal to y

You can even take x = 21 and y = 9
Top
User avatar
GMAT Instructor
Posts: 3225
Joined: Tue Jan 08, 2008 2:40 pm
Location: Toronto
Thanked: 1710 times
Followed by:614 members
GMAT Score:800

Re: silly ques

by Stuart@KaplanGMAT » Tue Nov 18, 2008 12:25 pm
vivek.kapoor83 wrote:If y ≠ 3 and 3x/y is a prime integer greater than 2, which of the following must be true?
Ⅰ. x = y
Ⅱ. y = 1
Ⅲ. x and y are prime integers.
(A) None
(B) Ⅰ only
(C) Ⅱonly
(D) Ⅲonly
(E) Ⅰand Ⅲ


I chose B. means if x=y , then expression would result in 3 always.So, I went for option B but OA is diff. I dont know where i am going wrong.
The question asks "which of the following MUST be true" - you showed that statement I COULD be true, which isn't the same thing.
Image

Stuart Kovinsky | Kaplan GMAT Faculty | Toronto

Kaplan Exclusive: The Official Test Day Experience | Ready to Take a Free Practice Test? | Kaplan/Beat the GMAT Member Discount
BTG100 for $100 off a full course
Top
Legendary Member
Posts: 2467
Joined: Thu Aug 28, 2008 6:14 pm
Thanked: 331 times
Followed by:11 members

by cramya » Tue Nov 18, 2008 3:35 pm
3x/y = 5 or 7 or 11

Lets take 3x/y = 5

x/y = 5/3

x and y could take on many values one being 20/12

x=20 y=12

All 3 statements are false. Like Stuart said since its a must be question and we have dosproved all 3 choices


P.S For MUST be TRUE questions if u can disprove a choice with one set of values then that choice will not be part of the correct answer

For COULD be TRUEquestions if u can prove that a choice is true for one set of values then that choice will be part of the correct answer

Hope this helps also!
A)
Top
Post new topic Post Reply
• Page 1 of 1