NEW HERE? LEARN MORE
closeclose
Last visit was: 25 Apr 2024, 05:20 It is currently 25 Apr 2024, 05:20
Decision Tracker
My Rewards
New posts
New comers' posts

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.
Go to My Error Log Learn more
Close
Request Expert Reply
Confirm Cancel

Is √(56x) an integer?

SORT BY:
Date
Kudos
Tags:
Find Similar Topics 
Show Tags
Hide Tags
User avatar
honchos
Senior Manager
Senior Manager
Joined: 17 Apr 2013
Status:Verbal Forum Moderator
Posts: 361
Own Kudos [?]: 2197 [3]
Given Kudos: 298
Location: India
GMAT 1: 710 Q50 V36
GMAT 2: 750 Q51 V41
GMAT 3: 790 Q51 V49
GPA: 3.3
Send PM
Is √(56x) an integer? [#permalink] New post   01 Dec 2013, 17:36
1
Kudos
2
Bookmarks
00:00
A
B
C
D
E

Difficulty:

55% (hard)

Question Stats:

60% (01:47) correct 40% (01:24) wrong based on 201 sessions
Hide Show timer Statistics
Is √(56x) an integer?

(1) x is a multiple of 14.
(2) 28 is not a factor of x.
ShowHide Answer
Official Answer
E
User avatar
L
Bunuel
Math Expert
Joined: 02 Sep 2009
Posts: 92912
Own Kudos [?]: 618924 [2]
Given Kudos: 81595
Send PM
CAT Tests Forum Quiz Mode
Re: Is √(56x) an integer? [#permalink] New post   02 Dec 2013, 02:06
1
Kudos
1
Bookmarks
Expert Reply
Is √(56x) an integer?

\(\sqrt{56x}=2\sqrt{14x}\).

(1) x is a multiple of 14. If x=14, then the answer is YES but if x=14*3, then the answer is NO. Not sufficient.

(2) 28 is not a factor of x. Consider the same examples. Not sufficient.

(1)+(2) Consider the same examples. Not sufficient.

Answer: E.
User avatar
jlgdr
VP
VP
Joined: 06 Sep 2013
Posts: 1345
Own Kudos [?]: 2391 [0]
Given Kudos: 355
Concentration: Finance
Schools: Wharton '17 (A) HBS '17 (WA$)
Send PM
GMAT ToolKit User
Re: Is √(56x) an integer? [#permalink] New post   06 Jan 2014, 10:16
honchos wrote:
Is √(56x) an integer?

(1) x is a multiple of 14.
(2) 28 is not a factor of x.


OK here's the deal

We need to know if X has at least 2 and a 7^2 for 56x to be a perfect square

Statement 1

Is a multiple of 2*7, OK, thanks for the info but we are still missing one 7

Statement 2

Not a factor of 2^2*7. Well OK, doesn't have a square power of 2 but could as well have a square power of 7. I need more info

Statement 1 and 2 together

Well we are still missing that 7!!

Answer is E

Cheers!
If it helps Kudos me ok?

J :)
User avatar
S
KrishnakumarKA1
Senior Manager
Senior Manager
Joined: 05 Jan 2017
Posts: 416
Own Kudos [?]: 284 [0]
Given Kudos: 15
Location: India
Send PM
Re: Is √(56x) an integer? [#permalink] New post   23 Feb 2017, 06:09
Prompt analysis
56x is an integer.

Superset
The answer will be either yes or no

Translation
In order to find the value of √(56x), we need
1# exact value of x
2# some property of x to assure the answer

Statement analysis
St 1: 56x = 8*7 x. X can be 14 or 28 for example and we will get different results. INSUFFICIENT
St 2: x can be 14 and 15. Different results. INSUFFICIENT.

St 1 & St 2: we can say that x is odd multiple of 14. We take two numbers. 42 and 126. We get different results. INSUFFICIENT

Option E
GMAT Club Bot
gmatclubot
Re: Is √(56x) an integer? [#permalink]
23 Feb 2017, 06:09
Moderator:
Bunuel
Math Expert
92912 posts

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne
Main navigation
GMAT Resources
Partners
MBA Resources
www.gmac.com|www.mba.com | | GMAT Club Rules | Terms and Conditions