It is currently 24 Feb 2018, 13:38

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

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

If the tens digit of positive integers x, y are 6, how many values of

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

Hide Tags

Expert Post
1 KUDOS received
Math Revolution GMAT Instructor
User avatar
D
Joined: 16 Aug 2015
Posts: 4908
GPA: 3.82
If the tens digit of positive integers x, y are 6, how many values of [#permalink]

Show Tags

New post 14 Mar 2016, 17:08
1
This post received
KUDOS
Expert's post
6
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  95% (hard)

Question Stats:

42% (01:21) correct 58% (01:31) wrong based on 142 sessions

HideShow timer Statistics

If the tens digit of positive integers x, y are 6, how many values of the tens digit of 2(x+y) can be there?

A. 2
B. 3
C. 4
D. 5
E. 6


* A solution will be posted in two days.
[Reveal] Spoiler: OA

_________________

MathRevolution: Finish GMAT Quant Section with 10 minutes to spare
The one-and-only World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy.
Find a 10% off coupon code for GMAT Club members.
“Receive 5 Math Questions & Solutions Daily”
Unlimited Access to over 120 free video lessons - try it yourself
See our Youtube demo

Expert Post
1 KUDOS received
Math Revolution GMAT Instructor
User avatar
D
Joined: 16 Aug 2015
Posts: 4908
GPA: 3.82
Re: If the tens digit of positive integers x, y are 6, how many values of [#permalink]

Show Tags

New post 17 Mar 2016, 17:20
1
This post received
KUDOS
Expert's post
2
This post was
BOOKMARKED
If the tens digit of positive integers x, y are 6, how many values of the tens digit of 2(x+y) can be there?

A. 2
B. 3
C. 4
D. 5
E. 6


-> If X=y=60, 2(x+y)=240 is derived. If x=y=69, 2(x+y)=276 is derived, which makes 4,5,6,7 possible for the tens digit. Therefore, the answer is C.
_________________

MathRevolution: Finish GMAT Quant Section with 10 minutes to spare
The one-and-only World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy.
Find a 10% off coupon code for GMAT Club members.
“Receive 5 Math Questions & Solutions Daily”
Unlimited Access to over 120 free video lessons - try it yourself
See our Youtube demo

Retired Moderator
avatar
B
Status: I Declare War!!!
Joined: 02 Apr 2014
Posts: 254
Location: United States
Concentration: Finance, Economics
GMAT Date: 03-18-2015
WE: Asset Management (Investment Banking)
GMAT ToolKit User Premium Member
Re: If the tens digit of positive integers x, y are 6, how many values of [#permalink]

Show Tags

New post 17 Jul 2016, 04:16
Hi!
did used a small layman method.. correct my approach (though crack down the answer correctly)
lets fix 6 for x
for y we have 1 .....9 = means 9 numbers
1+6 =7
2+6= 8
3+6= 9
4+6= 1 (10 but took 1 as for tens digit)
5+6 =1 (11... took 1 for tens digit)
...
..
.
so all 1 for tens digit hence same.

7,8,9,1 means 4 ...
correct me .
really interesting question.
Intern
Intern
avatar
B
Joined: 13 Sep 2015
Posts: 17
Re: If the tens digit of positive integers x, y are 6, how many values of [#permalink]

Show Tags

New post 22 Aug 2016, 01:22
I get 2 as ans.

If the sum of the units digits of X and Y is less than 9, then the tens digits of x+y is 2. When this sum is multiplied by the 2, the tens digit will become 4.

If the sum of the units digit of X and Y is more than 9, then the tens digit of x+y is 3, because maximum 1 can be carried over from units place and thus 6+1+6 will leave 3 in the tens place. 3*2 will leave 6 for 2(x+y).

Thus total 2 numbers in tens place for the operation 2(x+y)!!

please tell me where am i going wrong?
Manager
Manager
User avatar
Joined: 03 May 2014
Posts: 70
Concentration: Operations, Marketing
Schools: ISB '17 (D)
GMAT 1: 680 Q48 V34
GMAT 2: 700 Q49 V35
WE: Engineering (Energy and Utilities)
GMAT ToolKit User
Re: If the tens digit of positive integers x, y are 6, how many values of [#permalink]

Show Tags

New post 22 Aug 2016, 08:11
deeksha6 wrote:
I get 2 as ans.

If the sum of the units digits of X and Y is less than 9, then the tens digits of x+y is 2. When this sum is multiplied by the 2, the tens digit will become 4.

If the sum of the units digit of X and Y is more than 9, then the tens digit of x+y is 3, because maximum 1 can be carried over from units place and thus 6+1+6 will leave 3 in the tens place. 3*2 will leave 6 for 2(x+y).

Thus total 2 numbers in tens place for the operation 2(x+y)!!

please tell me where am i going wrong?


Hey you are missing something after multiplication that can be carry over.
_________________

Beat verbal, Beat GMAT...;)
Trying Hard to do that.....

Kudos if my post helped you

Intern
Intern
avatar
B
Joined: 13 Sep 2015
Posts: 17
Re: If the tens digit of positive integers x, y are 6, how many values of [#permalink]

Show Tags

New post 23 Aug 2016, 00:54
sahil7389 wrote:
deeksha6 wrote:
I get 2 as ans.

If the sum of the units digits of X and Y is less than 9, then the tens digits of x+y is 2. When this sum is multiplied by the 2, the tens digit will become 4.

If the sum of the units digit of X and Y is more than 9, then the tens digit of x+y is 3, because maximum 1 can be carried over from units place and thus 6+1+6 will leave 3 in the tens place. 3*2 will leave 6 for 2(x+y).

Thus total 2 numbers in tens place for the operation 2(x+y)!!

please tell me where am i going wrong?


Hey you are missing something after multiplication that can be carry over.


Yes! Thank you for pointing that out :)
Director
Director
User avatar
P
Joined: 28 Mar 2017
Posts: 895
CAT Tests
Re: If the tens digit of positive integers x, y are 6, how many values of [#permalink]

Show Tags

New post 12 Feb 2018, 08:12
MathRevolution wrote:
If the tens digit of positive integers x, y are 6, how many values of the tens digit of 2(x+y) can be there?

A. 2
B. 3
C. 4
D. 5
E. 6


* A solution will be posted in two days.


Minimum value possible = 60+60=120*2=240
Maximum value possible = 69+69=138*2=276
Thus, all values between 4 and 7 inclusive - 4,5,6 and 7 - can be present as tense digit.

Answer should be C
_________________

Kudos if my post helps!

Helpful links:
1. Useful Formulae, Concepts and Tricks-Quant
2. e-GMAT's ALL SC Compilation
3. LSAT RC compilation
4. Actual LSAT CR collection by Broal
5. QOTD RC (Carcass)
6. Challange OG RC

Re: If the tens digit of positive integers x, y are 6, how many values of   [#permalink] 12 Feb 2018, 08:12
Display posts from previous: Sort by

If the tens digit of positive integers x, y are 6, how many values of

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


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