January 17, 2019 January 17, 2019 08:00 AM PST 09:00 AM PST Learn the winning strategy for a high GRE score — what do people who reach a high score do differently? We're going to share insights, tips and strategies from data we've collected from over 50,000 students who used examPAL. January 19, 2019 January 19, 2019 07:00 AM PST 09:00 AM PST Aiming to score 760+? Attend this FREE session to learn how to Define your GMAT Strategy, Create your Study Plan and Master the Core Skills to excel on the GMAT.
Author 
Message 
TAGS:

Hide Tags

Manager
Joined: 06 Apr 2010
Posts: 117

If r, s, and w are positive numbers such that w = 60r + 80s
[#permalink]
Show Tags
12 Sep 2010, 06:25
Question Stats:
67% (01:07) correct 33% (01:08) wrong based on 227 sessions
HideShow timer Statistics
If r, s, and w are positive numbers such that w = 60r + 80s and r + s = 1, is w < 70? (1) r > 0.5 (2) r > s
Official Answer and Stats are available only to registered users. Register/ Login.



Intern
Joined: 18 Jul 2010
Posts: 44

Re: Inequality DS
[#permalink]
Show Tags
12 Sep 2010, 06:46
If w = 60r + 80s and r+s = 1 then it means that w = 60r + 60s + 20s = 60(r+s) + 20s = 60 + 20s
(1) r > 0.5 so, since r + s = 1, we knows that s < 0.5. so w = 60 + 20s < 60+ 20*0.5 = 60 + 10 = 0. So w < 70. SUFFICIENT
(2) This statement is the same as the first one. Indeed, r > s and r + s = 1 so s < 0.5.
Answer : D.



Manager
Joined: 06 Aug 2010
Posts: 172
Location: Boston

Re: Inequality DS
[#permalink]
Show Tags
13 Sep 2010, 05:53
udaymathapati wrote: If r, s, and w are positive numbers such that w = 60r + 80s and r + s = 1, is w < 70? (1) r > 0.5 (2) r > s 1 and 2 are exactly the same, so the answer is either (D) or (E). For #1: If r = 0.5, then w = (60*0.5) + (80*0.5) = 30 + 40 = 70. As r gets bigger, w gets smaller (because it's composed of a bigger fraction of 60 and a smaller fraction of 80  eg, if r = 0.9, s = 0.1 and w = 54+8 = 62), so w is definitely less than 70. Since 1 and 2 are the same, the answer is (D).



GMAT Tutor
Joined: 24 Jun 2008
Posts: 1323

Re: Inequality DS
[#permalink]
Show Tags
13 Sep 2010, 06:19
udaymathapati wrote: If r, s, and w are positive numbers such that w = 60r + 80s and r + s = 1, is w < 70? (1) r > 0.5 (2) r > s This is actually just a weighted average. Say at a company r is the fraction of employees who are men. Then s = 1r would be the fraction of all employees who are women. If men earn $60/hr and women earn $80/hr, then w = 60r + 80s would then just be the average wage of all employees. If there are more male employees than female employees, then the average wage must be less than $70/hr, so each statement is sufficient alone.
_________________
GMAT Tutor in Toronto
If you are looking for online GMAT math tutoring, or if you are interested in buying my advanced Quant books and problem sets, please contact me at ianstewartgmat at gmail.com



Director
Joined: 25 Apr 2012
Posts: 683
Location: India
GPA: 3.21
WE: Business Development (Other)

Re: If r, s, and w are positive numbers such that w = 60r + 80s
[#permalink]
Show Tags
29 Apr 2014, 20:51
udaymathapati wrote: If r, s, and w are positive numbers such that w = 60r + 80s and r + s = 1, is w < 70? (1) r > 0.5 (2) r > s Sol: Given r,s and w are positive nos and w=60r+80s and r+s=1 We need to know whether w<70 or not Given r+s=1 so 60r+60s=60> The given expression for w = 60r+60s+20s or w=60+20s The question becomes is 60+20s<70 or s<1/2 St 1: If r>0.5 then s<0.5 because r+s=1. Sufficient St 2: r>s. Okay it is given that r+s=1 so as r increases, s decreases and r=s=0.5. Since r>s therefore r has to greater than 0.5 and hence s < 0.5 Ans is D
_________________
“If you can't fly then run, if you can't run then walk, if you can't walk then crawl, but whatever you do you have to keep moving forward.”



NonHuman User
Joined: 09 Sep 2013
Posts: 9419

Re: If r, s, and w are positive numbers such that w = 60r + 80s
[#permalink]
Show Tags
24 Dec 2018, 14:31
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 Books  GMAT Club Tests  Best Prices on GMAT Courses  GMAT Mobile App  Math Resources  Verbal Resources




Re: If r, s, and w are positive numbers such that w = 60r + 80s &nbs
[#permalink]
24 Dec 2018, 14:31






