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

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

Algebra Expressions- Not so simple!

Expert replies
by Kemmy G » Wed Jun 15, 2011 12:39 pm
Can someone PLEASE explain question 148 of the 12 ed. OG quant section?
[x/x+y](10)+[y/x+y](20)= k.
What could be the value of k?

I've studied the explanation in the OG answer question and am still as stumped as ever. Can someone PLEASE explain it step by step, so it's really easy to follow and grasp?

Thanks, :)
Join the discussion
Source: — Problem Solving |

by Frankenstein » Wed Jun 15, 2011 1:23 pm
Hi,
Please post the complete question, including options. You haven't even posted the condition x<y and
x,y are positive numbers.


[x/x+y](10)+[y/x+y](20) = (10x+20y)/(x+y) = [10(x+y)+10y]/(x+y)
= 10[1 + (y/x+y)]
Given x < y => x+y < y+y
So, x+y < 2y => y/(x+y) > 1/2
and y/(x+y) < 1
So, 10[1 + (y/x+y)] > 10[1+ (1/2)] & 10[1 + (y/x+y)] < 10[1+ 1]
So, [x/x+y](10)+[y/x+y](20) > 15 & [x/x+y](10)+[y/x+y](20) < 20
So, any value between 15 and 20 could be the value of k.
Last edited by Frankenstein on Wed Jun 15, 2011 1:28 pm, edited 1 time in total.
Cheers!

Things are not what they appear to be... nor are they otherwise
Join the discussion

by pemdas » Wed Jun 15, 2011 1:27 pm
i'll try without looking up an official explanation
with our conditions given x<y and x,y,k>0 we set k=(10x+20y)/(x+y) and this is equivalent to 10+10y/(x+y); because 10y/(x+y) is more than 10/2 {x<y, hence x+y<2y} our answer can be in the interval (greater than 15 and less than 20), so it's d
Kemmy G wrote:Can someone PLEASE explain question 148 of the 12 ed. OG quant section?
[x/x+y](10)+[y/x+y](20)= k.
What could be the value of k?

I've studied the explanation in the OG answer question and am still as stumped as ever. Can someone PLEASE explain it step by step, so it's really easy to follow and grasp?

Thanks, :)
Success doesn't come overnight!
Join the discussion

by GMATGuruNY » Wed Jun 15, 2011 2:17 pm
Private tutor exclusively for the GMAT and GRE, with over 20 years of experience.
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.

As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.

For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
Student Review #2
Student Review #3
Join the discussion

by Kemmy G » Tue Aug 02, 2011 3:28 am
Thank you so much guys, especially GMATGuruNY!!!

I thought I would receive alerts in my email box whenever anyone replied to my post, and since none came, I simply assumed the question wasn't answered. Will have to improve on checking BTG more regularly, :D. Thanks again everyone.

Off to study and understand the question again!
Join the discussion