Last visit was: 22 Nov 2024, 03:44 It is currently 22 Nov 2024, 03:44

Close

GRE Prep 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 GRE 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
User avatar
Retired Moderator
Joined: 07 Jun 2014
Posts: 4812
Own Kudos [?]: 11194 [0]
Given Kudos: 0
GRE 1: Q167 V156
WE:Business Development (Energy and Utilities)
Send PM
avatar
Manager
Manager
Joined: 22 Feb 2018
Posts: 163
Own Kudos [?]: 214 [0]
Given Kudos: 0
Send PM
avatar
Manager
Manager
Joined: 15 Feb 2018
Posts: 53
Own Kudos [?]: 34 [0]
Given Kudos: 0
Send PM
User avatar
Retired Moderator
Joined: 07 Jun 2014
Posts: 4812
Own Kudos [?]: 11194 [0]
Given Kudos: 0
GRE 1: Q167 V156
WE:Business Development (Energy and Utilities)
Send PM
Re: 1/x + 1/y =6 [#permalink]
1
Expert Reply
FatemehAsgarinejad wrote:
The question is wrong!


Yeah.. Fixed my bad
User avatar
Retired Moderator
Joined: 07 Jun 2014
Posts: 4812
Own Kudos [?]: 11194 [0]
Given Kudos: 0
GRE 1: Q167 V156
WE:Business Development (Energy and Utilities)
Send PM
Re: 1/x + 1/y =6 [#permalink]
1
Expert Reply
Explanation

Using the Bowtie method, you find that \(\frac{x+y}{xy}\)=6.

By multiplying both sides of the second equation by \(\frac{-1}{2}\), you find that \(\frac{1}{6}=\frac{zy}{z+y}\).

Flipping both fractions yields \(\frac{z+y}{zy}=6\), and thus, \(\frac{z+y}{zy}=\frac{x+y}{xy}\).

Inspecting the two fractions, you may realize that z must equal x.

Alternatively, by applying the Bowtie again, you obtain \(\frac{y + x}{zy} = \frac{z + y}{xy}\), and thus \(zy^2 +
xyz = xyz + xy^2\), meaning \(zy^2 = xy^2\), or z = x, so the answer is choice (C).
avatar
Manager
Manager
Joined: 22 Feb 2018
Posts: 163
Own Kudos [?]: 214 [0]
Given Kudos: 0
Send PM
Re: 1/x + 1/y =6 [#permalink]
answer: C
1/x + 1/y = 6
(x + y) / xy = 6

-1/3 = -2 (zy/(z + y))
(z + y) / zy = 6

(x + y) / xy = (z + y) / zy
(x + y) / x = (z + y) / z
1 + y/x = 1 + y/z
y/x = y/z
1/x = 1/z
x = z
avatar
Manager
Manager
Joined: 28 Nov 2017
Posts: 56
Own Kudos [?]: 82 [0]
Given Kudos: 0
Send PM
Re: 1/x + 1/y =6 [#permalink]
Answer is C

Expand the 1st given Equation and you get 6 = x+y / xy

Expand the 2nd Eqn and you will get 1/6 = zy/y+z

Substitute the value of 6 from 1st Equation and you get the answer after cancelling the common terms both sides.
Prep Club for GRE Bot
Re: 1/x + 1/y =6 [#permalink]
Moderators:
GRE Instructor
84 posts
GRE Forum Moderator
37 posts
Moderator
1111 posts
GRE Instructor
234 posts

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