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

Redeem
TTP OnDemand GMAT Video Course
Featured Course

Target Test Prep GMAT OnDemand

Scott Woodbury-Stewart’s private virtual classroom — 400 hours of master-class video lessons for the GMAT Focus Edition.

  • 715+ score guarantee — highest in the industry (99th percentile)
  • 52 chapters · 1,500+ lessons · 4,000+ practice questions
  • 400 hours of video · 1,500+ instructor-led HD smartboard lessons
  • 300,000+ students accepted to Harvard, Stanford, Wharton, Booth & Sloan & more
  • 24/7 live support + weekly Zoom office hours with GMAT instructors
  • TTP AI Assist — 24/7 AI-powered virtual tutor for instant help
  • 1,200+ flashcards + AI-powered study assistant & daily calendar
  • OnDemand, LiveTeach & GMAT Bootcamp formats available
  • Also: GRE, SAT Math & Executive Assessment courses
  • MBA Admissions Consulting now available
  • 🏆 2025 EdTech Breakthrough Award: Test Prep Solution Provider of the Year
  • 200,000+ students served
  • 5-day free trial — $0 to start, no auto-billing, cancel anytime
★★★★★ 5.0 (559 reviews)
130-pt guarantee
$0 to start then $127/mo
Start Free 5-Day Trial Read 559 Reviews →

from GMATprep

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
Newbie | Next Rank: 10 Posts
Posts: 6
Joined: Wed Dec 13, 2006 4:50 am
by d77 » Thu Dec 14, 2006 11:09 am
Circular gears P and Q start roating at the same time at constant speeds.gear P makes 10 revolutions per minute and gear Q makes 40 revolutions per minute.
How many seconds after the gears start roating will gear Q have made exactly 6 more revolutions then gear p?

6
8
10
12
15
12
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Problem Solving |
User avatar
Senior | Next Rank: 100 Posts
Posts: 41
Joined: Fri Dec 15, 2006 9:23 amFollowed by: 1 member
Location: Greece

by thankont » Fri Dec 15, 2006 2:03 pm
One approach could be this :
first case 1/6 rev. per sec
second case 2/3 rev. per sec
if we substitute 12 sec we get 2 rev for first case and 8 rev for second
so difference is 6
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Master | Next Rank: 500 Posts
Posts: 354
Joined: Tue Jun 27, 2006 9:20 pmFollowed by: 5 members
Thanked: 11 times

by 800guy » Sat Dec 16, 2006 9:04 pm
thanks, thankont!
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
User avatar
Legendary Member
Posts: 2469
Joined: Thu Apr 20, 2006 12:09 pmFollowed by: 14 members
Location: BtG Underground
Thanked: 85 times

by aim-wsc » Mon Dec 18, 2006 10:27 am
May be a lil exp to answer:

Gear P has 10 revolution per min
& G Q has 40

that means ever one revolution of P, Q revolves around four times.

after 2 revolution of P, Q would have revolved around itself 8 times.
in other words would have made 6 more rotations.

P takes 1/10 mins for one revolution. therefore 12 secs for 2 revolution.
Answer 12
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 8136
Joined: Sat Apr 25, 2015 10:56 amFollowed by: 29 members
Location: Los Angeles, CA
Thanked: 43 times

by Scott@TargetTestPrep » Wed Jun 20, 2018 4:29 pm
d77 wrote:Circular gears P and Q start roating at the same time at constant speeds.gear P makes 10 revolutions per minute and gear Q makes 40 revolutions per minute.
How many seconds after the gears start roating will gear Q have made exactly 6 more revolutions then gear p?

6
8
10
12
15
As we can see, Gear Q makes 30 more revolutions per minute than Gear P does. So, we can set up the following proportion to solve for the number of seconds for Gear Q to make 6 more revolutions than Gear P does:

30 revolutions/1 minute = 6 revolutions/x seconds

We need for both denominators to have the same units. . Since 1 minute = 60 seconds, we can say:

30/60 = 6/x

Cross multiplying, we have:

30x = 360

x = 12

Answer: D

Scott Woodbury-Stewart
Founder and CEO
[email protected]

Image

See why Target Test Prep is rated 5 out of 5 stars on BEAT the GMAT. Read our reviews

ImageImage
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1