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 →

Geometry | OG 12

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
User avatar
Master | Next Rank: 500 Posts
Posts: 206
Joined: Sun Jun 24, 2012 5:44 pmFollowed by: 3 members
Thanked: 5 times
by [email protected] » Wed Sep 26, 2012 7:55 pm
The inside dimensions of a rectangular wooden box are 6 inches by 8 inches by 10 inches. A cylindricalcanister is to be placed inside the box so that it stands upright when the closed box rests on one of its six faces. Of all such canisters that could be used, what is the radius, in inches, of the one that has maximum volume?
(A) 3
(B) 4
(C) 5
(D) 6
(E) 8

I am not able to understand why cant we take 10 as the length so that radius becomes 5 and height is 8. giving us the maximum volume?
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Problem Solving |

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 3835
Joined: Fri Apr 02, 2010 10:00 pmFollowed by: 523 members
Location: Milpitas, CA
Thanked: 1854 times
GMAT Score:770

by Anurag@Gurome » Wed Sep 26, 2012 8:15 pm
[email protected] wrote:The inside dimensions of a rectangular wooden box are 6 inches by 8 inches by 10 inches. A cylindricalcanister is to be placed inside the box so that it stands upright when the closed box rests on one of its six faces. Of all such canisters that could be used, what is the radius, in inches, of the one that has maximum volume?
(A) 3
(B) 4
(C) 5
(D) 6
(E) 8

I am not able to understand why cant we take 10 as the length so that radius becomes 5 and height is 8. giving us the maximum volume?
Volume of cylinder = (pi) * radius² * height of cylinder
If the cylinder is placed on 6 in by 8 in. face, then it's maximum radius is 6/2 = 3 and volume will be (pi) * 3² * 10 = 90(pi)
If the cylinder is placed on 6 in by 10 in. face, then it's maximum radius is 6/2 = 3 and volume will be (pi) * 3² * 8 = 72(pi)
If the cylinder is placed on 8 in by 10 in. face, then it's maximum radius is 8/2 = 4 and volume will be (pi) * 4² * 6 = 96(pi)

We can see that the volume is maximum when radius = 4 in.

The correct answer is B.
Anurag Mairal, Ph.D., MBA
GMAT Expert, Admissions and Career Guidance
Gurome, Inc.
1-800-566-4043 (USA)

Join Our Facebook Groups
GMAT with Gurome
https://www.facebook.com/groups/272466352793633/
Admissions with Gurome
https://www.facebook.com/groups/461459690536574/
Career Advising with Gurome
https://www.facebook.com/groups/360435787349781/
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1