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

It is currently 22 Oct 2019, 07:10

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 3^7 – 3^5 = (2^x)(3^y), where x and y are integers, what is x + y?

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

Hide Tags

Find Similar Topics 
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 58432
If 3^7 – 3^5 = (2^x)(3^y), where x and y are integers, what is x + y?  [#permalink]

Show Tags

New post 22 Jan 2019, 01:02
00:00
A
B
C
D
E

Difficulty:

  15% (low)

Question Stats:

82% (00:53) correct 18% (01:31) wrong based on 36 sessions

HideShow timer Statistics

VP
VP
User avatar
D
Joined: 31 Oct 2013
Posts: 1465
Concentration: Accounting, Finance
GPA: 3.68
WE: Analyst (Accounting)
CAT Tests
Re: If 3^7 – 3^5 = (2^x)(3^y), where x and y are integers, what is x + y?  [#permalink]

Show Tags

New post 22 Jan 2019, 01:05
Bunuel wrote:
If \(3^7 – 3^5 = (2^x)(3^y)\), where x and y are integers, what is x + y?

A 2
B 3
C 8
D 15
E 243



Given,

\(3^7 – 3^5 = (2^x)(3^y)\)

\(3^5(3^2 -1) = 2^x3^y\)

\(3^5 2^3 = 2^x3^y\)

x= 3 and y= 5.

x + y = 3 + 5 = 8.

C is the correct answer.
Manager
Manager
avatar
B
Joined: 09 Nov 2015
Posts: 57
Concentration: Strategy, Technology
WE: Information Technology (Computer Software)
GMAT ToolKit User Reviews Badge
Re: If 3^7 – 3^5 = (2^x)(3^y), where x and y are integers, what is x + y?  [#permalink]

Show Tags

New post 22 Jan 2019, 01:16
3^5(3^2-1)=(2^x)(3^y)
3^5 2^3 =(2^x)(3^y)
x=3
y=5

answer is 8

Posted from my mobile device
GMAT Club Legend
GMAT Club Legend
User avatar
D
Joined: 18 Aug 2017
Posts: 5031
Location: India
Concentration: Sustainability, Marketing
GPA: 4
WE: Marketing (Energy and Utilities)
GMAT ToolKit User Premium Member
Re: If 3^7 – 3^5 = (2^x)(3^y), where x and y are integers, what is x + y?  [#permalink]

Show Tags

New post 22 Jan 2019, 04:43
Bunuel wrote:
If \(3^7 – 3^5 = (2^x)(3^y)\), where x and y are integers, what is x + y?

A 2
B 3
C 8
D 15
E 243


solve expression we get :
2^x*3^y = 3^5*2^3
x+y = 8
IMO C
GMAT Club Bot
Re: If 3^7 – 3^5 = (2^x)(3^y), where x and y are integers, what is x + y?   [#permalink] 22 Jan 2019, 04:43
Display posts from previous: Sort by

If 3^7 – 3^5 = (2^x)(3^y), where x and y are integers, what is x + y?

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





Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne