NEW HERE? LEARN MORE
closeclose
Last visit was: 25 Apr 2024, 03:04 It is currently 25 Apr 2024, 03:04
Decision Tracker
My Rewards
New posts
New comers' posts

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.
Go to My Error Log Learn more
Close
Request Expert Reply
Confirm Cancel

If xy > 0, 1/x + 1/y = 5, and 1/xy = 6, then (x+y)/5 = ?

SORT BY:
Date
Kudos
Tags:
Find Similar Topics 
Show Tags
Hide Tags
User avatar
L
Bunuel
Math Expert
Joined: 02 Sep 2009
Posts: 92912
Own Kudos [?]: 618893 [6]
Given Kudos: 81595
Send PM
CAT Tests Forum Quiz Mode
If xy > 0, 1/x + 1/y = 5, and 1/xy = 6, then (x+y)/5 = ? [#permalink] New post   09 Nov 2015, 23:02
2
Kudos
4
Bookmarks
Expert Reply
00:00
A
B
C
D
E

Difficulty:

25% (medium)

Question Stats:

70% (01:21) correct 30% (01:51) wrong based on 211 sessions
Hide Show timer Statistics
If xy > 0, 1/x + 1/y = 5, and 1/xy = 6, then (x+y)/5 = ?

A. 1/25
B. 1/6
C. 1/5
D. 5
E. 6
ShowHide Answer
Official Answer
B
avatar
HarrishGowtham
Intern
Intern
Joined: 29 Aug 2015
Posts: 7
Own Kudos [?]: 20 [0]
Given Kudos: 8
Send PM
Re: If xy > 0, 1/x + 1/y = 5, and 1/xy = 6, then (x+y)/5 = ? [#permalink] New post   10 Nov 2015, 08:58
Answer is B.

(1/X+1/Y)=5 canbe solved as {(x+y)/xy}=6. Substituting for 1/xy=6, we get
x+y=5/6

==> (x+y)/5= 5/(6*5)=1/6.
User avatar
L
generis
Senior SC Moderator
Joined: 22 May 2016
Posts: 5330
Own Kudos [?]: 35486 [0]
Given Kudos: 9464
Send PM
CAT Tests
If xy > 0, 1/x + 1/y = 5, and 1/xy = 6, then (x+y)/5 = ? [#permalink] New post   23 Oct 2017, 10:14
Expert Reply
Bunuel wrote:
If xy > 0, 1/x + 1/y = 5, and 1/xy = 6, then (x+y)/5 = ?

A. 1/25
B. 1/6
C. 1/5
D. 5
E. 6

HarrishGowtham wrote:
Answer is B.

(1/X+1/Y)=5 canbe solved as {(x+y)/xy}=6. Substituting for 1/xy=6, we get
x+y=5/6

==> (x+y)/5= 5/(6*5)=1/6.

I am stuck trying to understand this explanation. I got the right answer, but not this way.

\(\frac{1}{x}+ \frac{1}{y} = 5\)

\((\frac{1}{x}+ \frac{1}{y}) = \frac{x + y}{xy}\)

Aren't the two RHS equivalent?

Quote:
(1/X+1/Y)=5 can be solved as {(x+y)/xy}=6.


Can anyone explain the steps from the first part of the above sentence to the last part? If the two RHS above quote are equivalent, where does "= 6" come from?
User avatar
L
MikeScarn
Current Student
Joined: 04 Sep 2017
Status:Booth 1Y
Posts: 278
Own Kudos [?]: 1162 [0]
Given Kudos: 228
Location: United States (IL)
Concentration: Technology, Leadership
Schools: Tuck '24 (WA) Harvard '24 (D) Kellogg '24 (WA) Wharton '24 (D) Haas '24 (D) Sloan '24 (D) Fuqua '24 (D) Booth '24 (M) Yale '24 (A$)
GMAT 1: 690 Q44 V41
GMAT 2: 730 Q50 V38
GPA: 3.62
WE:Sales (Computer Software)
Send PM
Re: If xy > 0, 1/x + 1/y = 5, and 1/xy = 6, then (x+y)/5 = ? [#permalink] New post   02 Apr 2018, 16:10
Bunuel wrote:
If xy > 0, 1/x + 1/y = 5, and 1/xy = 6, then (x+y)/5 = ?

A. 1/25
B. 1/6
C. 1/5
D. 5
E. 6


Bunuel, will you please provide the solution?

I don't understand the solution above either. Thanks in advance.
User avatar
L
Bunuel
Math Expert
Joined: 02 Sep 2009
Posts: 92912
Own Kudos [?]: 618893 [0]
Given Kudos: 81595
Send PM
CAT Tests Forum Quiz Mode
Re: If xy > 0, 1/x + 1/y = 5, and 1/xy = 6, then (x+y)/5 = ? [#permalink] New post   02 Apr 2018, 20:52
Expert Reply
msurls wrote:
Bunuel wrote:
If xy > 0, 1/x + 1/y = 5, and 1/xy = 6, then (x+y)/5 = ?

A. 1/25
B. 1/6
C. 1/5
D. 5
E. 6


Bunuel, will you please provide the solution?

I don't understand the solution above either. Thanks in advance.


\(\frac{1}{x} + \frac{1}{y} = 5\);

\(\frac{x+y}{xy} = 5\);

Since given that \(\frac{1}{xy}= 6\), then \(6(x+y)=5\).

Divide by 30: \(\frac{x+y}{5}=\frac{1}{6}\).

Answer: B.
avatar
B
Tommy87HG
Intern
Intern
Joined: 27 Jun 2017
Posts: 16
Own Kudos [?]: 0 [0]
Given Kudos: 4
GMAT 1: 680 Q43 V40
GMAT 2: 710 Q47 V41
Send PM
GMAT ToolKit User
If xy > 0, 1/x + 1/y = 5, and 1/xy = 6, then (x+y)/5 = ? [#permalink] New post   10 Apr 2018, 09:03
Bunuel wrote:
msurls wrote:
Bunuel wrote:
If xy > 0, 1/x + 1/y = 5, and 1/xy = 6, then (x+y)/5 = ?

A. 1/25
B. 1/6
C. 1/5
D. 5
E. 6


Bunuel, will you please provide the solution?

I don't understand the solution above either. Thanks in advance.


\(\frac{1}{x} + \frac{1}{y} = 5\);

\(\frac{x+y}{xy} = 5\);

Since given that \(\frac{1}{xy}= 6\), then \(6(x+y)=5\).

Divide by 30: \(\frac{x+y}{5}=\frac{1}{6}\).

Answer: B.


My approach is pretty similar:

\(\frac{1}{x} + \frac{1}{y} = 5\);

\(\frac{x+y}{xy} = 5\);

\(\frac{x+y}{5} = XY\);

\(\frac{1}{xy} = 6\) --> XY = \(;\frac{1}{6}\);

so

\(\frac{x+y}{5} = XY = 1/6\);
GMAT Club Bot
gmatclubot
If xy > 0, 1/x + 1/y = 5, and 1/xy = 6, then (x+y)/5 = ? [#permalink]
10 Apr 2018, 09:03
Moderators:
Bunuel
Math Expert
92912 posts
yashikaaggarwal
Senior Moderator - Masters Forum
3137 posts

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne
Main navigation
GMAT Resources
Partners
MBA Resources
www.gmac.com|www.mba.com | | GMAT Club Rules | Terms and Conditions