Live GMAT classes with Target Test Prep start Nov 21 and Nov 22. First class free.

See classes
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.

Newsweek Readers’ Choice Awards 2026 winner: Target Test Prep, #1 Test Prep

Target Test Prep was voted #1 Best Test Prep in the 2026 Newsweek Readers’ Choice™ Awards.

★★★★★5.0563 reviews
GMATLiveTeachStarts Nov 22
Josh Braslow, Target Test Prep GMAT expert
LIVE ONLINE CLASSES

Get Ready for GMAT Test Day Faster with Live Online Classes

with Josh Braslow, 20+ years in test prep

Nov 22 · Josh Braslow
Sun · 9:30 AM to 12:30 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
EALiveTeachOnDemandStart anytime
EXECUTIVE ASSESSMENT

Target Test Prep EA OnDemand

Self-paced EA prep. Study on your schedule.

EXECUTIVE ASSESSMENT

with

165+ EA score guarantee
$05-day trial no automatic billing
Schedule
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
GMATOnDemandStart 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 563 reviewsTarget Test Prep

One more quest from %

Expert replies
Post new topic Post Reply
Subscribe topic
Previous Topic Next Topic
Senior | Next Rank: 100 Posts
Posts: 65
Joined: Thu Jul 02, 2009 10:38 pm
Location: Bangalore
Thanked: 1 times
by engg.manik » Mon Sep 28, 2009 4:09 am
q---> a company sells z numbers of products, price of each product is y. In order to have revenue unchange by what percentage should the sales increase if the price falls down by 20%.

Can someone explain how to hit these kind of questions.
Thanks in advance.
Top
Join the discussion
Source: — Problem Solving |
Master | Next Rank: 500 Posts
Posts: 177
Joined: Thu Aug 14, 2008 11:59 am
Thanked: 25 times

by mp2437 » Mon Sep 28, 2009 6:09 am
See example you posted earlier. In general,

R = z*y, where R is revenue. If you want to have the same R, and you decrease one variable, the other must increase to compensate. Therefore:

R = z * y
R = z * (1 + x) * y (1 - .2), where x is the percentage increase that is necessary to compensate.

It is always better to use numbers for examples like these, so lets use 100, and z = 25, y = 4.

Since y is going down by 20%, its new price is 4*(1-.2) = 3.20. Now you know that R = 100 (since it is unchanged), and a new price of 3.20, so you could find z by:

R = z_new * y_new --> z_new = R / y_new = 100 / 3.20 = 31.25.

so z goes from 25 to 31.25. The percent increase is equal to (31.25 - 25)/25 = 25%.
Top
Join the discussion