GMAT Question of the Day - Daily to your Mailbox; hard ones only

It is currently 24 May 2019, 10:52

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

Is the integer x a 3-digit integer? (1) x is the square of an integer

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

Hide Tags

 
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 55271
Is the integer x a 3-digit integer? (1) x is the square of an integer  [#permalink]

Show Tags

New post 26 Apr 2019, 01:58
00:00
A
B
C
D
E

Difficulty:

  5% (low)

Question Stats:

85% (00:50) correct 15% (00:59) wrong based on 112 sessions

HideShow timer Statistics

Director
Director
User avatar
D
Joined: 18 Jul 2018
Posts: 906
Location: India
Concentration: Finance, Marketing
WE: Engineering (Energy and Utilities)
Premium Member Reviews Badge
Re: Is the integer x a 3-digit integer? (1) x is the square of an integer  [#permalink]

Show Tags

New post 26 Apr 2019, 09:49
1
From S1:

x is the square of an integer.
Clearly Insufficient.

From S2:

90 < x < 150
X can 91 or 100
Hence, Insufficient.

Combining both:

9^2 = 81
10^2 = 100
But, 81 doesn't lie between 90 < x < 150.
Hence X will be a 3 digit integer.
Sufficient.

C is the answer.
_________________
Press +1 Kudo If my post helps!
CEO
CEO
User avatar
P
Joined: 18 Aug 2017
Posts: 3531
Location: India
Concentration: Sustainability, Marketing
GPA: 4
WE: Marketing (Energy and Utilities)
GMAT ToolKit User Premium Member CAT Tests
Re: Is the integer x a 3-digit integer? (1) x is the square of an integer  [#permalink]

Show Tags

New post 27 Apr 2019, 05:44
Bunuel wrote:
Is the integer x a 3-digit integer?

(1) x is the square of an integer.
(2) 90 < x < 150


DS01602.01
OG2020 NEW QUESTION


#1
x can be single, double or triple digit insufficient
#2
90 < x < 150
double or triple digit
insufficient
from 1 &2
x=100 only possible for 10 , in range >90
IMO C
_________________
If you liked my solution then please give Kudos. Kudos encourage active discussions.
CEO
CEO
User avatar
V
Joined: 12 Sep 2015
Posts: 3727
Location: Canada
Re: Is the integer x a 3-digit integer? (1) x is the square of an integer  [#permalink]

Show Tags

New post 28 Apr 2019, 07:51
Top Contributor
Bunuel wrote:
Is the integer x a 3-digit integer?

(1) x is the square of an integer.
(2) 90 < x < 150


DS01602.01
OG2020 NEW QUESTION


Target question: Is the integer x a 3-digit integer?

Statement 1: x is the square of an integer.
Let's TEST some values.
There are several values of x that satisfy statement 1. Here are two:
Case a: x = 10² = 100. In this case, the answer to the target question is YES, x IS a 3-digit integer
Case b: x = 9² = 81. In this case, the answer to the target question is NO, x is NOT a 3-digit integer
Since we cannot answer the target question with certainty, statement 1 is NOT SUFFICIENT

Statement 2: 90 < x < 150
TEST some cases.
Case a: x = 100. In this case, the answer to the target question is YES, x IS a 3-digit integer
Case b: x = 91. In this case, the answer to the target question is NO, x is NOT a 3-digit integer
Since we cannot answer the target question with certainty, statement 2 is NOT SUFFICIENT

Statements 1 and 2 combined
There are THREE values of x that satisfy BOTH statements: x = 100, x = 121 and x = 144
In all three cases, the answer to the target question is the same: YES, x IS a 3-digit integer
Since we can answer the target question with certainty, the combined statements are SUFFICIENT

Answer: C

Cheers,
Brent
_________________
Test confidently with gmatprepnow.com
Image
EMPOWERgmat Instructor
User avatar
V
Status: GMAT Assassin/Co-Founder
Affiliations: EMPOWERgmat
Joined: 19 Dec 2014
Posts: 14198
Location: United States (CA)
GMAT 1: 800 Q51 V49
GRE 1: Q170 V170
Re: Is the integer x a 3-digit integer? (1) x is the square of an integer  [#permalink]

Show Tags

New post 28 Apr 2019, 13:02
Hi All,

We're told that X is an integer. We're asked if X is a 3-digit integer. This question can be solved by TESTing VALUES.

(1) X is the SQUARE of an INTEGER.

Fact 1 tells us that X is a 'perfect square.' For example, X could be 1, 4, 9.....100, 121, 144....10,000, etc.
IF....
X = 1, then the answer to the question is NO.
X = 100, then the answer to the question is YES.
Fact 1 is INSUFFICIENT

(2) 90 < X < 150

Fact 2 gives us a range of possible values for X.
IF....
X = 91, then the answer to the question is NO.
X = 100, then the answer to the question is YES.
Fact 2 is INSUFFICIENT

Combined, we know...
X is the SQUARE of an INTEGER.
90 < X < 150

There are only a few perfect squares in this given range: 100, 121 and 144. Regardless of which value X actually is, the answer to the question is ALWAYS YES.
Combined, SUFFICIENT

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

*****Select EMPOWERgmat Courses now include ALL 6 Official GMAC CATs!*****

Rich Cohen

Co-Founder & GMAT Assassin

Special Offer: Save $75 + GMAT Club Tests Free
  Official GMAT Exam Packs + 70 Pt. Improvement Guarantee
www.empowergmat.com/
Manager
Manager
User avatar
S
Joined: 25 Jul 2018
Posts: 50
Location: Uzbekistan
Concentration: Finance, Organizational Behavior
GMAT 1: 690 Q49 V35
GRE 1: Q168 V167
GPA: 3.85
WE: Project Management (Investment Banking)
CAT Tests
Re: Is the integer x a 3-digit integer? (1) x is the square of an integer  [#permalink]

Show Tags

New post 29 Apr 2019, 01:15
Bunuel wrote:
Is the integer x a 3-digit integer?

(1) x is the square of an integer.
(2) 90 < x < 150


DS01602.01
OG2020 NEW QUESTION


Hola amigos :cool:

Is the integer x a 3-digit integer?

1. \(x\) is the square of an integer.
if \(x = 1\), then \(x^2 = 1\), the answer is NOT
if \(x = 10\), then \(x^2 = 100\), the answer is YES
Insufficient

2. 90 < \(x\) < 150
if \(x = 95\), then the answer is NOT
if \(x = 145\), then the answer is YES
Insufficient

1 + 2. \(x\) can be any integer from \(91\) to \(149\). if \(x = 91\), then \(x^2 = 91*91\). \(91*91\) is greater than \(90*90 = 8100\), thus it is not a 3-digit integer. Hence at any value greater then \(91\), \(x\) will not be a 3-digit integer.
Sufficient. C
_________________
Let's help each other with kudos. Kudos will be payed back ;)
Target Test Prep Representative
User avatar
D
Status: Founder & CEO
Affiliations: Target Test Prep
Joined: 14 Oct 2015
Posts: 6231
Location: United States (CA)
Re: Is the integer x a 3-digit integer? (1) x is the square of an integer  [#permalink]

Show Tags

New post 02 May 2019, 17:24
Bunuel wrote:
Is the integer x a 3-digit integer?

(1) x is the square of an integer.
(2) 90 < x < 150


DS01602.01
OG2020 NEW QUESTION


We need to determine whether integer x is a 3-digit integer.

Statement One Alone

x is the square of an integer.

Even though we know that x is a square, we cannot determine whether it’s a 3-digit integer. For example, if x = 10^2 = 100, then x is a 3-digit integer. However, if x = 5^2 = 25, then it is NOT a 3-digit integer.

Statement one alone is not sufficient to answer the question.

Statement Two Alone:

90 < x < 150

Since x could be either a 2-digit integer (e.g., 95) or a 3-digit integer (e.g., 105), statement two alone is not sufficient to answer the question.

Statements One and Two Together:

The perfect squares between 90 and 150 are 100, 121, and 144. Thus, we see that x must be a 3-digit integer.

Answer: C
_________________

Scott Woodbury-Stewart

Founder and CEO

Scott@TargetTestPrep.com
TTP - Target Test Prep Logo
122 Reviews

5-star rated online GMAT quant
self study course

See why Target Test Prep is the top rated GMAT quant course on GMAT Club. Read Our Reviews

If you find one of my posts helpful, please take a moment to click on the "Kudos" button.

e-GMAT Representative
User avatar
D
Joined: 04 Jan 2015
Posts: 2873
Is the integer x a 3-digit integer? (1) x is the square of an integer  [#permalink]

Show Tags

New post 14 May 2019, 05:26

Solution



Steps 1 & 2: Understand Question and Draw Inferences

In this question, we are given
    • The number x is an integer

We need to determine
    • Whether x is a 3-digit integer or not.

To determine whether x is a 3-digit integer or not, we need to know the value of x, or any specific range of x from which a unique value of number of digits of x can be determined.
With this information, let’s now analyse the individual statements.

Step 3: Analyse Statement 1

As per the information given in statement 1, x is the square of an integer.
From this statement, it is not possible to determine the number of digits of x.
    • If x = 22 = 4, then x is a single-digit integer.
    • If x = 52 = 25, then x is a double-digit integer.
    • If x = 122 = 144, then x is a three-digit integer.

Hence, statement 1 is not sufficient to answer the question.

Step 4: Analyse Statement 2

As per the information given in statement 2, 90 < x < 150.

In this given range, there can be two possibilities.
    • For 90 < x < 100:
      o The integer x has two digits.
    • For 100 ≤ x < 150:
      o The integer x has three digits.

As we cannot determine whether x is a 3-digit integer or not, statement 2 is not sufficient to answer the question.

Step 5: Combine Both Statements Together (If Needed)

From statements 1 and 2 together, we get
    • The integer x is the square of an integer.
    • Also, 90 < x < 150

Now, in the given range, the possible square numbers are 100, 121 and 144.
    • x can be any one of these 3 values.
    • Also, all these 3 numbers have 3 digits, implies x is a 3-digit integer
.

Hence, the correct answer choice is option C.

Image

_________________
GMAT Club Bot
Is the integer x a 3-digit integer? (1) x is the square of an integer   [#permalink] 14 May 2019, 05:26
Display posts from previous: Sort by

Is the integer x a 3-digit integer? (1) x is the square of an integer

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


cron
Copyright

GMAT Club MBA Forum Home| About| Terms and Conditions and Privacy Policy| 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®.