Last visit was: 12 Dec 2024, 12:45 It is currently 12 Dec 2024, 12:45
Home
GMAT
Messages
Tests
Schools
Reviews
Social
Chat
My Profile
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
Back to Forum
Create Topic
Sub 505 Level|   Algebra|      
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 12 Dec 2024
Posts: 97,848
Own Kudos:
685,373
Given Kudos: 88,255
Products:
GMAT Club Tests Forum Quiz
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 97,848
Kudos: 685,373
If a/b = −2/3, then (b − a)/a = Updated on: 08 Jul 2019, 05:37
Originally posted by Bunuel on 31 May 2017, 12:45.
Last edited by Sajjad1994 on 08 Jul 2019, 05:37, edited 1 time in total.
Added Source
Kudos
Add Kudos
Bookmarks
Bookmark this Post
00:00
Start Timer
Pause Timer
Resume Timer
Show Answer
Hide
Show
History
A
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!

Difficulty:

5% (low)

Question Stats:

89% (00:53) correct 11% (01:32) wrong based on 54 sessions

History

Date
Time
Result
Not Attempted Yet
If \(\frac{a}{b} = −\frac{2}{3}\), then \(\frac{b − a}{a} =\)

(A) − 5/2
(B) − 5/3
(C) − 1/3
(D) 0
(E) 7

Source: Nova GMAT
Difficulty Level: 550
ShowHide Answer
Official Answer
A
User avatar
pushpitkc
User avatar
Joined: 26 Feb 2016
Last visit: 24 Apr 2024
Posts: 2,856
Own Kudos:
5,582
Given Kudos: 47
Location: India
GPA: 3.12
Posts: 2,856
Kudos: 5,582
If a/b = −2/3, then (b − a)/a = 31 May 2017, 12:50
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Assume values a=-4 and b=6(which are in the ratio)

(b-a)/a
= (6 -(-4))/-4
= 10/-4
= -5/2(Option A)


Sent from my ONEPLUS A3003 using GMAT Club Forum mobile app
avatar
sjavvadi
avatar
Joined: 03 Oct 2013
Last visit: 24 May 2018
Posts: 56
Own Kudos:
73
Given Kudos: 16
Posts: 56
Kudos: 73
If a/b = −2/3, then (b − a)/a = 31 May 2017, 15:13
Kudos
Add Kudos
Bookmarks
Bookmark this Post
a/b = -2/3

=> b/a = -3/2
Subtract 1 on both sides

b-a/a = -5/2
User avatar
sashiim20
User avatar
Joined: 04 Dec 2015
Last visit: 05 Jun 2024
Posts: 620
Own Kudos:
1,682
 []
Given Kudos: 276
Location: India
Concentration: Technology, Strategy
Schools: ISB '19 IIMB IIMA XLRI HEC Sept19 intake Rotman '21 NUS '21 NTU '20 Trinity MBA '20 Bocconi '21 Smurfit "21
WE:Information Technology (Consulting)
Schools: ISB '19 IIMB IIMA XLRI HEC Sept19 intake Rotman '21 NUS '21 NTU '20 Trinity MBA '20 Bocconi '21 Smurfit "21
Posts: 620
Kudos: 1,682
 []
If a/b = −2/3, then (b − a)/a = 31 May 2017, 16:50
2
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Bunuel
If \(\frac{a}{b} = −\frac{2}{3}\), then \(\frac{b − a}{a} =\)

(A) − 5/2
(B) − 5/3
(C) − 1/3
(D) 0
(E) 7

Method 1:
\(\frac{b − a}{a}\)
Simplifying the fraction we get; \(\frac{b − a}{a}\) = \(\frac{b}{a}\) - \(\frac{a}{a}\)
= \(\frac{b}{a}\) - 1 -----------------(i)

Given; \(\frac{a}{b} = −\frac{2}{3}\)
\(\frac{b}{a}\) = \(−\frac{3}{2}\) --------------- (ii)

Substituting the value of (ii) in the equation (i)
\(−\frac{3}{2}\) -1 = \(\frac{(-3-2)}{2}\) = \(\frac{-5}{2}\)
Answer A...



Method 2:
\(\frac{a}{b} = −\frac{2}{3}\)
a = \(−\frac{2}{3}\)b
Substituting value of a in the equation \(\frac{b − a}{a} =\)
\((b-(\frac{-2}{3})b) / (\frac{-2}{3})b\)

= \((b + (\frac{2}{3})b) / - (\frac{2}{3})b\)

= (\(\frac{3b + 2b}{3}) / - (\frac{2}{3})b\)

= \((\frac{5b}{3}) / - (\frac{2}{3})b\) = \(\frac{-5}{2}\)
Answer A...
User avatar
mohshu
User avatar
Joined: 21 Mar 2016
Last visit: 26 Dec 2019
Posts: 448
Own Kudos:
127
Given Kudos: 103
Products:
My Reviews
Posts: 448
Kudos: 127
If a/b = −2/3, then (b − a)/a = 01 Jun 2017, 07:25
Kudos
Add Kudos
Bookmarks
Bookmark this Post
simplify (b-a/a)
gives (b/a) - 1 = (-3/2) - 1
= -5/2
ans A
avatar
obliraj
avatar
Joined: 26 Jul 2016
Last visit: 17 Apr 2019
Posts: 35
Own Kudos:
24
Given Kudos: 21
Location: India
Schools: NTU '20 (S)  (S) NUS '21 (S) IIMA PGPX"20 (D) IIMC PGPEX"20 (A)
Schools: NTU '20 (S)  (S) NUS '21 (S) IIMA PGPX"20 (D) IIMC PGPEX"20 (A)
Posts: 35
Kudos: 24
If a/b = −2/3, then (b − a)/a = 01 Jun 2017, 08:47
Kudos
Add Kudos
Bookmarks
Bookmark this Post
(b-a)/a= (b/a)-1
(-3/2)-1= -5/2
Answer A
avatar
GovindAgrawal077
avatar
Joined: 23 May 2017
Last visit: 08 Jun 2017
Posts: 5
Posts: 5
Kudos: 0
If a/b = −2/3, then (b − a)/a = 02 Jun 2017, 20:55
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Bunuel
If \(\frac{a}{b} = −\frac{2}{3}\), then \(\frac{b − a}{a} =\)

(A) − 5/2
(B) − 5/3
(C) − 1/3
(D) 0
(E) 7

we are given the ratio of a:b as 2:3. if we break the required equation we get: b/a - a/a. So, fianally we need to find b/a - 1. Therefore, we get b/a -1 = -3/2 -1 = -5/2. Therefore, the ans is A.
User avatar
ScottTargetTestPrep
User avatar
Target Test Prep Representative
Joined: 14 Oct 2015
Last visit: 12 Dec 2024
Posts: 19,862
Own Kudos:
24,268
Given Kudos: 288
Status:Founder & CEO
Affiliations: Target Test Prep
Location: United States (CA)
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 19,862
Kudos: 24,268
If a/b = −2/3, then (b − a)/a = 05 Jun 2017, 16:07
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Bunuel
If \(\frac{a}{b} = −\frac{2}{3}\), then \(\frac{b − a}{a} =\)

(A) − 5/2
(B) − 5/3
(C) − 1/3
(D) 0
(E) 7

We are given that a/b = -2/3, so:

3a = -2b

-3a/2 = b

Thus, (b - a)/a is:

[(-3a/2) - a]/a

[(-3a/2) - (2a/2)]/a

(-5a/2)/a = -5a/2a = -5/2

Answer: A
Moderator:
Bunuel
Math Expert
97848 posts