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

It is currently 23 Jul 2018, 08:50

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

If 18 < x < 68, is the integer x even?

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

Hide Tags

Expert Post
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 47221
If 18 < x < 68, is the integer x even?  [#permalink]

Show Tags

New post 09 Mar 2016, 13:06
00:00
A
B
C
D
E

Difficulty:

  75% (hard)

Question Stats:

51% (01:07) correct 49% (01:24) wrong based on 55 sessions

HideShow timer Statistics

If 18 < x < 68, is the integer x even?

(1) Neither the tens digit nor the units digits of x is prime.
(2) Sum of the tens digit and units digit of x is prime.

_________________

New to the Math Forum?
Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

Intern
Intern
avatar
Joined: 03 Mar 2016
Posts: 3
GMAT ToolKit User
If 18 < x < 68, is the integer x even?  [#permalink]

Show Tags

New post Updated on: 09 Mar 2016, 15:22
According to how i went on solving this, i got the answer as C.

1) neither units nor tens digit is prime.

=> it is composite
=> possible numbers for both - 4,6,8,9
which will give numbers such as 44, 46, 48, 49 - here you get both even and odd => not sufficient

2) Sum of tens and units digit is prime
=> possible tens digit nos - 1,2,3,4,5,6,
possible units digit nos- 1,2,3,5,6,7,8,9,0

=> some of the numbers are - 20,21,25,29,32 .. - here again you get both even and odd => not sufficient

1)+2)
=> possible number for tens and units places - 4,6
possible number for units places - 4,6,8,9
sum of tens and units digits is prime
=> will give only one answer 13 (49; 4+9 =13) odd => x is not even

Answer: C

Originally posted by PSV01 on 09 Mar 2016, 13:24.
Last edited by PSV01 on 09 Mar 2016, 15:22, edited 1 time in total.
Manager
Manager
User avatar
Joined: 15 Feb 2016
Posts: 62
GMAT 1: 710 Q48 V40
Reviews Badge
If 18 < x < 68, is the integer x even?  [#permalink]

Show Tags

New post Updated on: 12 Mar 2016, 10:17
Bunuel wrote:
If 18 < x < 68, is the integer x even?

(1) Neither the tens digit nor the units digits of x is prime.
(2) Sum of the tens digit and units digit of x is prime.


I was able to do this in half a minute but took me 15 minutes to try to write down the thinking process. Writing confused me :lol:

Will give writing a shot nevertheless

Tens can be 2,3,4,5,6 Units can be anything from 0 to 9 plus number 19

Statement 1

Forget 10s digit, the units digit can be 1,4,6,8,9
clearly, x can be odd or ever
Not sufficient

Statement 2

Prime sum options 21,23,25,32 etc
Since these are both odd and even numbers
Not sufficient

Together
realising that 2 can not be the units digit (since it is prime) 4,6,or 8 in units will sum up to prime numbers only when ten's digit is prime. So can't be.

Possible values
19,41,49,61

Only Odd

Hence C

Correction in the posted Question - Neither the tens digit nor the units digit s of x is prime.
_________________

It is not who I am underneath but what I do that defines me.


Originally posted by KarishmaParmar on 09 Mar 2016, 13:48.
Last edited by KarishmaParmar on 12 Mar 2016, 10:17, edited 1 time in total.
Intern
Intern
avatar
Joined: 03 Mar 2016
Posts: 3
GMAT ToolKit User
Re: If 18 < x < 68, is the integer x even?  [#permalink]

Show Tags

New post 09 Mar 2016, 15:13
KarishmaParmar

Though you have arrived at the same answer like me :) Don't forget that 1 is neither prime nor composite
Intern
Intern
avatar
B
Joined: 30 Aug 2017
Posts: 18
Location: India
Schools: ISB '19 (A)
GMAT 1: 670 Q47 V35
GPA: 3.9
Re: If 18 < x < 68, is the integer x even?  [#permalink]

Show Tags

New post 06 Oct 2017, 23:40
PSV01 wrote:
KarishmaParmar

Though you have arrived at the same answer like me :) Don't forget that 1 is neither prime nor composite


The question says the number is not prime. It does not say that the number is not composite. Hence 1 should be included.
Intern
Intern
avatar
B
Joined: 30 Aug 2017
Posts: 18
Location: India
Schools: ISB '19 (A)
GMAT 1: 670 Q47 V35
GPA: 3.9
Re: If 18 < x < 68, is the integer x even?  [#permalink]

Show Tags

New post 06 Oct 2017, 23:41
KarishmaParmar wrote:
Bunuel wrote:
If 18 < x < 68, is the integer x even?

(1) Neither the tens digit nor the units digits of x is prime.
(2) Sum of the tens digit and units digit of x is prime.


I was able to do this in half a minute but took me 15 minutes to try to write down the thinking process. Writing confused me :lol:

Will give writing a shot nevertheless

Tens can be 2,3,4,5,6 Units can be anything from 0 to 9 plus number 19

Statement 1

Forget 10s digit, the units digit can be 1,4,6,8,9
clearly, x can be odd or ever
Not sufficient

Statement 2

Prime sum options 21,23,25,32 etc
Since these are both odd and even numbers
Not sufficient

Together
realising that 2 can not be the units digit (since it is prime) 4,6,or 8 in units will sum up to prime numbers only when ten's digit is prime. So can't be.

Possible values
19,41,49,61- 19 should not be included here. 10 is not a prime.
Only Odd

Hence C

Correction in the posted Question - Neither the tens digit nor the units digit s of x is prime.
Re: If 18 < x < 68, is the integer x even? &nbs [#permalink] 06 Oct 2017, 23:41
Display posts from previous: Sort by

If 18 < x < 68, is the integer x even?

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

Events & Promotions

PREV
NEXT


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®.