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

Redeem

Target Test Prep · GMAT

Choose how you want to prepare

Learn live with an expert or move at your own pace. Every option includes the complete TTP study system.

★★★★★5.0559 reviews
GMATLiveTeach Starts Oct 17
Chris Peckover, Target Test Prep GMAT expert
LIVE ONLINE CLASSES

Get Ready for GMAT Test Day Faster with Live Online Classes

with Chris Peckover, 100th-Percentile GMAT Scorer

Oct 17 · Chris Peckover
Sat · 11:00 AM to 2:00 PM ET
Oct 20 · Chris Peckover
Tue, Thu · 8:00 to 10:00 PM ET
Oct 25 · Josh Braslow
Sun · 1:00 to 4:00 PM ET
Included
40 hours of live online classes + 6 months of TTP OnDemand
  • Attend the first class for free
  • Every class is recorded, so you never fall behind
View classes & enroll
Limited seats availableTarget Test Prep
EALiveTeachOnDemand 5 seats left Start anytime
EXECUTIVE ASSESSMENT

Target Test Prep EA OnDemand

Self-paced EA prep. Study on your schedule.

Logan Thompson
EXECUTIVE ASSESSMENT

Sep 6 to Dec 6, 2026

with Logan Thompson

165+ EA score guarantee
$05-day trial no automatic billing
Schedule
Sun · 9:30 AM to 12:30 PM ET
Included
40 hours of live online classes plus six months of access to the complete TTP EA OnDemand course.
  • 165+ EA Score Guarantee
  • 4,100+ Quant, Verbal, and Integrated Reasoning practice questions
  • 400+ hours of in-depth video lessons
  • 3,000+ step-by-step video solutions
View EA class & enroll Start free 5-day trial
Limited cohort · enrollment openTrial includes full course accessTarget Test Prep
GMATOnDemand Start anytime
SELF-PACED MASTERCLASS

Target Test Prep GMAT OnDemand

Complete access from day one. Study on your schedule.

715+ score guarantee
$0to start then $127/mo
  • Personalized study plan and analytics
  • Thousands of lessons and practice questions
Start free 5-day trial
Read 559 reviewsTarget Test Prep

Compare the format, schedule, and included access before enrolling. Prices and seat counts shown reflect the supplied offer details.

Ratio - applied algenra problem

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
Senior | Next Rank: 100 Posts
Posts: 62
Joined: Thu Jul 03, 2008 4:52 am
by [email protected] » Mon Jul 21, 2008 12:08 pm
Hi

Can someone please help me understand the answer explanation to problem 97 in the Problem solving section of the OG 11. I have not typed the problem out but if you need me to just let me know.

thanks in advance
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Problem Solving |
Legendary Member
Posts: 661
Joined: Tue Jul 08, 2008 12:58 pm
Location: France
Thanked: 48 times

by pepeprepa » Mon Jul 21, 2008 12:36 pm
You could write the question :wink:
Water consists of hydrogen and oxygen, and the approximate ratio, by mass, of hydrogen to oxygen is 2:16. Approximately how many grams of oxygen are there in 144 grams of water?

A)16
B)72
C)112
D)128
E)142


We know that for every gram of hydrogen we have 8 grams of oxygen (that is the same as 2:16)
So we also know that in 9 grams of mass, there is 1 gram of H and 8 grams of O. So we understand that 8/9 of the mass is oxygen.
There are 144 grams of water.
We want the number of grams of oxygen in the 144 and we have the ratio of 8/9
We do: 144*8/9=128

D)128

Hope it helps you more than the book.
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Senior | Next Rank: 100 Posts
Posts: 62
Joined: Thu Jul 03, 2008 4:52 am

by [email protected] » Mon Jul 21, 2008 1:14 pm
Great thanks very much for your response
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
User avatar
Legendary Member
Posts: 566
Joined: Fri Jan 04, 2008 11:01 am
Location: Philadelphia
Thanked: 31 times
GMAT Score:640

by AleksandrM » Mon Jul 21, 2008 2:30 pm
2x + 16x = 144

x = 8

8 * 16 = 128
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Senior | Next Rank: 100 Posts
Posts: 58
Joined: Fri Jul 18, 2008 12:26 pm
Thanked: 2 times

by malolakrupa » Thu Jul 24, 2008 9:16 am
Shoudnt the answer be 16 grams of oxygen , becuase in 9 grams of water there is 1 gram of oxygen and 8 grams of hydrogen. so in 144 grams of water there will be 144 / 9 grams of oxygen which is 16
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Newbie | Next Rank: 10 Posts
Posts: 1
Joined: Wed Jun 08, 2011 7:05 pm

by shreyatagra » Mon Jun 20, 2011 7:59 pm
AleksandrM wrote:2x + 16x = 144

x = 8

8 * 16 = 128

Why a single variable for mass of 2 different components ?? Actually I also solved it this way, later realized I cannot take x for both Hydrogen and Oxygen.
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 3835
Joined: Fri Apr 02, 2010 10:00 pmFollowed by: 523 members
Location: Milpitas, CA
Thanked: 1854 times
GMAT Score:770

by Anurag@Gurome » Mon Jun 20, 2011 9:11 pm
malolakrupa wrote:Shoudnt the answer be 16 grams of oxygen , becuase in 9 grams of water there is 1 gram of oxygen and 8 grams of hydrogen. so in 144 grams of water there will be 144 / 9 grams of oxygen which is 16

It is just the reverse. In 9 grams of water, there is 1 gram of hydrogen and 8 grams of oxygen.
So, in 144 grams of water there will be (8/9) * 144 = 128 grams of oxygen.
Anurag Mairal, Ph.D., MBA
GMAT Expert, Admissions and Career Guidance
Gurome, Inc.
1-800-566-4043 (USA)

Join Our Facebook Groups
GMAT with Gurome
https://www.facebook.com/groups/272466352793633/
Admissions with Gurome
https://www.facebook.com/groups/461459690536574/
Career Advising with Gurome
https://www.facebook.com/groups/360435787349781/
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Master | Next Rank: 500 Posts
Posts: 401
Joined: Tue May 24, 2011 1:14 amFollowed by: 5 members
Thanked: 37 times

by MBA.Aspirant » Mon Jun 20, 2011 9:23 pm
pepeprepa wrote:You could write the question :wink:
Water consists of hydrogen and oxygen, and the approximate ratio, by mass, of hydrogen to oxygen is 2:16. Approximately how many grams of oxygen are there in 144 grams of water?

A)16
B)72
C)112
D)128
E)142
H:O:Total
2:16:18
..: x: 144

x = 144*16/18= 128
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1