Last visit was: 25 Apr 2024, 03:17 It is currently 25 Apr 2024, 03:17

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
SORT BY:
Date
Tags:
Show Tags
Hide Tags
Math Expert
Joined: 02 Sep 2009
Posts: 92912
Own Kudos [?]: 618897 [5]
Given Kudos: 81595
Send PM
Senior Manager
Senior Manager
Joined: 11 May 2014
Status:I don't stop when I'm Tired,I stop when I'm done
Posts: 474
Own Kudos [?]: 38825 [2]
Given Kudos: 220
Location: Bangladesh
Concentration: Finance, Leadership
GPA: 2.81
WE:Business Development (Real Estate)
Send PM
avatar
Intern
Intern
Joined: 27 May 2013
Posts: 10
Own Kudos [?]: 68 [0]
Given Kudos: 12
Concentration: Finance, Entrepreneurship
Send PM
SVP
SVP
Joined: 20 Mar 2014
Posts: 2362
Own Kudos [?]: 3626 [0]
Given Kudos: 816
Concentration: Finance, Strategy
GMAT 1: 750 Q49 V44
GPA: 3.7
WE:Engineering (Aerospace and Defense)
Send PM
Re: If b 0 and a > b, is a > c? (1) a/b> c/b (2) 5ab > 6bc [#permalink]
rohankant12 wrote:
Statement 1 - a/b> c/b
If you multiply both sides by b, you get a>c. Thus, sufficient

Statement 2 - 5ab > 6bc
1) Divide both sides by b --> 5a>6c
2) You get a/b > 6/5

Thus sufficient

Answer is D


Be extremely careful with multiplying with variables in inequality questions when you do not know the signs. In this case, you dont know whether b<0 or >0. The sign of inequality changes when you multiply the inequality by a negative number.

Thus, the method to solve it is:

a/b > c/b --> (a-c)/b > 0 ---> 2 cases; either a-c>0 and b>0 or a-c<0 and b<0. Thus you get 2 cases , making statement as NOT SUFFICIENT.

You can even test some numbers.

Per statement 2, 5ab > 6bc, again you can not divide by b as you do not know the sign of 'b'.

5ab > 6bc ---> b(5a-6c) >0 again, 2 cases : either b >0 and 5a-6c>0 or b<0 and 5a-6c <0. NOT SUFFICIENT.

Even when you combine 2 statements, you still can not figure out the sign of b , giving E as the correct answer.
User avatar
Non-Human User
Joined: 09 Sep 2013
Posts: 32665
Own Kudos [?]: 821 [0]
Given Kudos: 0
Send PM
Re: If b 0 and a > b, is a > c? (1) a/b> c/b (2) 5ab > 6bc [#permalink]
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
GMAT Club Bot
Re: If b 0 and a > b, is a > c? (1) a/b> c/b (2) 5ab > 6bc [#permalink]
Moderator:
Math Expert
92912 posts

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