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

MGMAT a satellite is composed of

Expert replies
by rommysingh » Thu Sep 03, 2015 12:08 pm
A satellite is composed of 30 modular units, each of which is equipped with a set of sensors, some of which have been upgraded. Each unit contains the same number of non-upgraded sensors. If the number of non-upgraded sensors on one unit is 1/5 the total number of upgraded sensors on the entire satellite, what fraction of the sensors on the satellite have been upgraded?



5/6


1/5


1/6


1/7


1/24
Join the discussion
Source: — Problem Solving |

by Brent@GMATPrepNow » Thu Sep 03, 2015 12:14 pm
A satellite is composed of 30 modular units, each of which is equipped with a set of sensors, some of which have been upgraded. Each unit contains the same number of non-upgraded sensors. If the number of non-upgraded sensors on one unit is 1/5 the total number of upgraded sensors on the entire satellite, what fraction of the sensors on the satellite have been upgraded?

A)5/6
B)1/5
C)1/6
D)1/7
E)1/2
Since we're asked to find a certain FRACTION, we can plug in some nice values that meet the given conditions.

Let's say that there's a TOTAL of 5 upgraded sensors on the entire satellite

the number of non-upgraded sensors on one modular unit is 1/5 the TOTAL number of upgraded sensors on the entire satellite
So, the number of non-upgraded sensors on EACH modular unit = (1/5)(5) = 1.

Since there are 30 modular units altogether, the TOTAL number of non-upgraded sensors = (30)(1) = 30.

So, the TOTAL number of sensors = (number of non-upgrades) + (number of upgraded)
= 30 + 5
= 35

What fraction of the sensors on the satellite have been upgraded?
= 5/35
= [spoiler]1/7[/spoiler]
= D

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

by Poisson » Sat Jun 11, 2016 6:18 am
Hello,

I'm having a hard time following the calculations for this. Could someone share an algebraic approach to answering this question? Thanks so much
Join the discussion

by Gmatasap » Sat Jun 11, 2016 8:15 am
Poisson wrote:Hello,

I'm having a hard time following the calculations for this. Could someone share an algebraic approach to answering this question? Thanks so much
Let N be the number of Non Upgraded sensors in each unit. Total Non upgraded sensors will be 30N
Let T.U be the total Upgraded sensors, then

N=1/5(T.U)
or 5N= T.U

Now ratio of Total upgraded to Total sensors is,

T.U/(TU+30N)
=5N/(5N+30N)
=[spoiler]1/7[/spoiler]

IMO D
Join the discussion