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

A sphere is inscribed in a cube

Expert replies
Post new topic Post Reply
Subscribe topic
Previous Topic Next Topic
Master | Next Rank: 500 Posts
Posts: 186
Joined: Sat Dec 24, 2016 12:38 amFollowed by: 3 members
Thanked: 5 times
by rsarashi » Sun May 07, 2017 4:14 am
A sphere is inscribed in a cube with an edge of 10. What is the shortest possible distance from one of the vertices of the cube to the surface of the sphere?

A) 10(underroot 3 – 1)

B) 5

C) 10(underroot 2 – 1)

D) 5(underroot 3 – 1)

E) 5(underroot 2 – 1)

OAD
Top
Join the discussion
Source: — Problem Solving |

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 3008
Joined: Mon Aug 22, 2016 6:19 amFollowed by: 34 members
Location: Grand Central / New York
Thanked: 470 times

by Jay@ManhattanReview » Sun May 07, 2017 5:08 am
rsarashi wrote:A sphere is inscribed in a cube with an edge of 10. What is the shortest possible distance from one of the vertices of the cube to the surface of the sphere?

A) 10(underroot 3 – 1)

B) 5

C) 10(underroot 2 – 1)

D) 5(underroot 3 – 1)

E) 5(underroot 2 – 1)

OAD
Since the length of the edge = 10, diameter of the inscribed sphere = 10

The shortest possible distance from one of the vertices of the cube to the surface of the sphere = 1/2 of [Distance from one vertex to the diagonally opposite vertex - Diameter of the sphere] = 1/2[10√3 - 10] = [spoiler]5[√3 - 1][/spoiler]

The correct answer: D

Hope this helps!

Relevant book: Manhattan Review GMAT Geometry Guide

-Jay
_________________
Manhattan Review GMAT Prep

Locations: New York | Vienna | Kuala Lumpur | Sydney | and many more...

Schedule your free consultation with an experienced GMAT Prep Advisor! Click here.
Top
Join the discussion
Master | Next Rank: 500 Posts
Posts: 186
Joined: Sat Dec 24, 2016 12:38 amFollowed by: 3 members
Thanked: 5 times

by rsarashi » Mon May 08, 2017 8:55 am

The shortest possible distance from one of the vertices of the cube to the surface of the sphere = 1/2 of [Distance from one vertex to the diagonally opposite vertex - Diameter of the sphere] = 1/2[10√3 - 10] = [spoiler]5[√3 - 1][/spoiler]
Hi Jay ,

Thank you so much for your reply.

I really don't understand the above part.

Can you please explain?

Thanks.
Top
Join the discussion
User avatar
GMAT Instructor
Posts: 15539
Joined: Tue May 25, 2010 12:04 pmFollowed by: 1906 members
Location: New York, NY
Thanked: 13060 times
GMAT Score:790

by GMATGuruNY » Mon May 08, 2017 8:58 am
I provide a visual solution here:
https://www.beatthegmat.com/geometry-que ... 76729.html
Private tutor exclusively for the GMAT and GRE, with over 20 years of experience.
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.

As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.

For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
Student Review #2
Student Review #3
Top
Join the discussion