It is currently 16 Dec 2018, 21:51
My Tests

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.

a and b are the digits of a two- digit number ab, and b = a

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
Moderator
Moderator
User avatar
Joined: 18 Apr 2015
Posts: 5199
Followers: 77

Kudos [?]: 1048 [0], given: 4690

CAT Tests
a and b are the digits of a two- digit number ab, and b = a [#permalink] New post 14 Apr 2018, 02:24
Expert's post
00:00

Question Stats:

43% (00:50) correct 56% (01:08) wrong based on 23 sessions
a and b are the digits of a two- digit number ab, and b = a + 3.

Quantity A
Quantity B
The positive two-digit number \(ab\)
The positive two-digit number \(ba\)


A. The quantity in Column A is greater
B. The quantity in Column B is greater
C. The two quantities are equal
D. The relationship cannot be determined from the information given
[Reveal] Spoiler: OA

_________________

Get the 2 FREE GREPrepclub Tests

1 KUDOS received
Director
Director
User avatar
Joined: 07 Jan 2018
Posts: 555
Followers: 4

Kudos [?]: 482 [1] , given: 84

CAT Tests
Re: a and b are the digits of a two- digit number ab, and b = a [#permalink] New post 15 Apr 2018, 00:24
1
This post received
KUDOS
Given that \(ab\) is a two digit number \(a\) cannot be \(0\) since \(0b = b\)

so probable values for \(a =1,2,3,4,5,6\)
\(a\) cannot also be more than \(6\) since a is an integer and adding \(3\) to \(7\) or more will make b a two digit number in itself which is not possible
for every given value of \(a\) in the list in order, \(b = 4,5,6,7,8,9\)

so \(ab = 14,25,36,47,58,69\)
hence, \(ba = 41,52,63,74,85,96\)

comparing \(ab\) to \(ba\) according to the respective \(1st-6th\) term above
B>A
_________________

This is my response to the question and may be incorrect. Feel free to rectify any mistakes

1 KUDOS received
Intern
Intern
Joined: 05 Jun 2017
Posts: 8
Followers: 0

Kudos [?]: 7 [1] , given: 0

Re: a and b are the digits of a two- digit number ab, and b = a [#permalink] New post 23 Apr 2018, 14:13
1
This post received
KUDOS
Side A:
we are given b = a + 3
ab can be written as
10*a + b
=10a + a + 3
11a + 3

Side B:
ba can be written as
10b + a
= 10(a+3) + a
= 11a + 30

Therefore Side B is greater
Re: a and b are the digits of a two- digit number ab, and b = a   [#permalink] 23 Apr 2018, 14:13
Display posts from previous: Sort by

a and b are the digits of a two- digit number ab, and b = a

  Question banks Downloads My Bookmarks Reviews Important topics  


GRE Prep Club Forum Home| About| Terms and Conditions and Privacy Policy| GRE Prep Club Rules| Contact

Powered by phpBB © phpBB Group

Kindly note that the GRE® test is a registered trademark of the Educational Testing Service®, and this site has neither been reviewed nor endorsed by ETS®.