BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem
TTP OnDemand GMAT Video Course
Featured Course

Target Test Prep GMAT OnDemand

Scott Woodbury-Stewart’s private virtual classroom — 400 hours of master-class video lessons for the GMAT Focus Edition.

  • 715+ score guarantee — highest in the industry (99th percentile)
  • 52 chapters · 1,500+ lessons · 4,000+ practice questions
  • 400 hours of video · 1,500+ instructor-led HD smartboard lessons
  • 300,000+ students accepted to Harvard, Stanford, Wharton, Booth & Sloan & more
  • 24/7 live support + weekly Zoom office hours with GMAT instructors
  • TTP AI Assist — 24/7 AI-powered virtual tutor for instant help
  • 1,200+ flashcards + AI-powered study assistant & daily calendar
  • OnDemand, LiveTeach & GMAT Bootcamp formats available
  • Also: GRE, SAT Math & Executive Assessment courses
  • MBA Admissions Consulting now available
  • 🏆 2025 EdTech Breakthrough Award: Test Prep Solution Provider of the Year
  • 200,000+ students served
  • 5-day free trial — $0 to start, no auto-billing, cancel anytime
★★★★★ 5.0 (559 reviews)
130-pt guarantee
$0 to start then $127/mo
Start Free 5-Day Trial Read 559 Reviews →

A contractor

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
Master | Next Rank: 500 Posts
Posts: 275
Joined: Wed Jul 02, 2008 4:19 am
Thanked: 4 times
by Xbond » Fri Aug 14, 2009 12:21 am
Hi there,

I would like to know the simplest process to resolve this DS. Explanation is requested.

A contractor combined x tons of a gravel mixture that contained 10 percent gravel G, by weight, with y tons of a mixture that contained 2 percent gravel G, by weight, to produce z tons of a mixture that was 5 percent gravel G by weight. What is the value of x ?

(1) y = 10
(2) z = 16
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Data Sufficiency |
Newbie | Next Rank: 10 Posts
Posts: 9
Joined: Fri Mar 27, 2009 4:12 am
Thanked: 1 times

by pavell » Fri Aug 14, 2009 12:33 am
E?
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Legendary Member
Posts: 752
Joined: Sun May 17, 2009 11:04 pm
Location: Tokyo
Thanked: 81 times
GMAT Score:680

by tohellandback » Fri Aug 14, 2009 12:55 am
IMO C
the equation you get is

.1X+.02Y=.05Z
we need both Y and Z to get X

hence C
The powers of two are bloody impolite!!
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Master | Next Rank: 500 Posts
Posts: 159
Joined: Sun Jul 27, 2008 8:41 pm
Thanked: 3 times

by ankit1383 » Fri Aug 14, 2009 2:16 am
tohellandback wrote:IMO C
the equation you get is

.1X+.02Y=.05Z
we need both Y and Z to get X

hence C
.1X + .02Y=.05(X+Y)

since Z is made up of both X and Y
or this thing we cnt assume????

If we follow the above equation the answer is D
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Legendary Member
Posts: 752
Joined: Sun May 17, 2009 11:04 pm
Location: Tokyo
Thanked: 81 times
GMAT Score:680

by tohellandback » Fri Aug 14, 2009 2:19 am
ankit1383 wrote:
tohellandback wrote:IMO C
the equation you get is

.1X+.02Y=.05Z
we need both Y and Z to get X

hence C
.1X + .02Y=.05(X+Y)

since Z is made up of both X and Y
or this thing we cnt assume????

If we follow the above equation the answer is D
thanks. you are right. I missed that.
answer must be D
The powers of two are bloody impolite!!
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Master | Next Rank: 500 Posts
Posts: 275
Joined: Wed Jul 02, 2008 4:19 am
Thanked: 4 times

by Xbond » Fri Aug 14, 2009 12:02 pm
how do you find the value of x with statement 2 in order to say D is right answer :

.1X + .02Y=.05(X+Y)
.1X + .02Y=.05(Z)
.1X + .02Y=.05(16)
.1X + .02Y=8

at the end you have 2 differents variables except whether you assume X+Y =8+8, no ?
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Master | Next Rank: 500 Posts
Posts: 275
Joined: Wed Jul 02, 2008 4:19 am
Thanked: 4 times

by Xbond » Fri Aug 14, 2009 12:04 pm
how do you find the value of x with statement 2 in order to say D is right answer :

.1X + .02Y=.05(X+Y)
.1X + .02Y=.05(Z)
.1X + .02Y=.05(16)
.1X + .02Y=8

at the end you have 2 differents variables except whether you assume X+Y =8+8, no ?
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Legendary Member
Posts: 708
Joined: Sun Jun 01, 2008 4:59 amFollowed by: 1 member
Location: USA
Thanked: 13 times

by niraj_a » Fri Aug 14, 2009 1:59 pm
Xbond,

can't Y be equal to 1-X?
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Junior | Next Rank: 30 Posts
Posts: 23
Joined: Sun Jun 21, 2009 10:30 am
Thanked: 2 times

by anand0408 » Sat Aug 15, 2009 2:46 am
Y is Z-X

So you have 2 eqns and 2 variables
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Master | Next Rank: 500 Posts
Posts: 275
Joined: Wed Jul 02, 2008 4:19 am
Thanked: 4 times

by Xbond » Mon Aug 17, 2009 5:15 am
many thks guys

OA is D
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Senior | Next Rank: 100 Posts
Posts: 43
Joined: Thu Mar 12, 2009 8:56 pmFollowed by: 1 member
Thanked: 10 times
GMAT Score:730

by jjk » Mon Aug 17, 2009 3:48 pm
Yes, Y is simply Z - X.

If we replace Y with Z - X in the equation, we get:

.10X + .02(16 - X) = .8

X = 6
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1