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.

★★★★★5.0563 reviews
Newsweek Readers’ Choice Awards 2026 winner: Target Test Prep, #1 Test Prep
NEWSWEEK READERS’ CHOICE AWARDS 2026

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

GMATLiveTeach Starts Oct 25
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

Oct 25 · Josh Braslow
Sun · 1:00 to 4:00 PM ET
Nov 8 · 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
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 563 reviewsTarget Test Prep

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

average

Expert replies
Post new topic Post Reply
Subscribe topic
Previous Topic Next Topic
Junior | Next Rank: 30 Posts
Posts: 27
Joined: Sat Jan 28, 2012 8:22 amFollowed by: 1 member
by klaud » Tue Feb 21, 2012 6:50 am
A college chemistry course is divided in two sections. In section A, the average score was 92,while, in section B, the average score was 84. If the average score of all 40 students was 89, how many students are in section A?
Top
Join the discussion
Source: — Problem Solving |

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 16207
Joined: Mon Dec 08, 2008 6:26 pmFollowed by: 1268 members
Location: Vancouver, BC
Thanked: 5254 times
GMAT Score:770

by Brent@GMATPrepNow » Tue Feb 21, 2012 8:54 am
klaud wrote:A college chemistry course is divided in two sections. In section A, the average score was 92,while, in section B, the average score was 84. If the average score of all 40 students was 89, how many students are in section A?
Main principle: If the mean of X numbers is M, then the sum of all X numbers is XM

Let A = # of students in class A
Let B = # of students in class B

Sum of scores in class A = 92A (since the mean is 92)
Sum of scores in class B = 84B (since the mean is 84)
Sum of scores in classes A and B combined = (89)(40) (since the mean is 89 and there are 40 students)
. . . So, 92A + 84B = (89)(40)

We also know that A + B = 40 (40 students in total)

Now we solve the system of equations:
92A + 84B = (89)(40)
A + B = 40

Multiply both sides of blue equation by 84 to get
92A + 84B = (89)(40)
84A + 84B = (84)(40)

Subtract blue equation from green equation to get: 8A = (5)(40)
Divide both sides by 8 to get: A = (5)(5) = 25

There are 25 students in section A

Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
Image
Top
Join the discussion