Geometry question

Expert replies

jnellaz: Master | Next Rank: 500 Posts; Posts: 114; Joined: Mon Oct 20, 2008 7:03 pmFollowed by: 5 members; Thanked: 4 times

by jnellaz » Sat Nov 08, 2008 9:01 am

Here is one:

A perfectly spherical satellite with a radius of 4 feet is being packed for shipment to its launch site. If the inside dimensions of the rectangular crates available for shipment, when measured in feet, are consecutive even integers, then what is the volume of the smallest available crate that can be used? (note: The volume of a sphere is given by the equation V = 4/3(3.14)r^3.

a. 48
b. 192
c. 480
d. 960
e. 1680

[spoiler]Answer is D: 960[/spoiler][spoiler][/spoiler]

Like this post

Source: Beat The GMAT — Problem Solving | Sat Nov 08, 2008 9:01 am

dmateer25: Community Manager; Posts: 1049; Joined: Sun Apr 06, 2008 5:15 pmFollowed by: 27 members; Location: Pittsburgh, PA; Thanked: 113 times; GMAT Score:710

by dmateer25 » Sat Nov 08, 2008 9:12 am

My approach:

Radius is 4 for the sphere. Diameter is 8.

Need a box that with dimensions ATLEAST 8 ft long, ATLEAST 8 ft wide, and ATLEAST 8 ft tall

The crates inside dimensions are consecutive even integers.

The smallest crate to satisfy the above is a crate that is 8 x 10 x 12

V=8*10*12 = 960

Like this post

iamcste: Legendary Member; Posts: 940; Joined: Tue Aug 26, 2008 3:22 amFollowed by: 1 member; Thanked: 55 times

IMO D

by iamcste » Sat Nov 08, 2008 9:14 am

Smallest size of the crate are 8,10 and 12

and the volume of the rectangle=8*10*12=960

I simply went by the choices to factorize it to 3 consecutive integers

Also, if you calculate volume of the sphere , it is around 256

so options A, B get eliminate¨

you cannot factorize 480 to 3 consecutive even integers

There could be better way, but this is mine

Like this post

raunekk: Legendary Member; Posts: 1159; Joined: Wed Apr 16, 2008 10:35 pm; Thanked: 56 times

by raunekk » Sat Nov 08, 2008 9:31 am

My approach:

Radius is 4 for the sphere. Diameter is 8.

Need a box that with dimensions ATLEAST 8 ft long, ATLEAST 8 ft wide, and ATLEAST 8 ft tall

The crates inside dimensions are consecutive even integers.

The smallest crate to satisfy the above is a crate that is 8 x 10 x 12

V=8*10*12 = 960

nice approach,,,

But then, is there no need or use to find the volume of the sphere ????

Like this post

Post new topic Post Reply

• Page 1 of 1

GMAT Course Reviews

560 reviews

1168 reviews

431 reviews

359 reviews

147 reviews

5/5

5 Star (560 Reviews)

"Target Test Prep is the closest to the official version of the GMAT exam, about 99% accuracy in terms of the quality and quantity of information. The course has excellently created singular sets of focused lessons and tests for every possible topic that one could come across in the official GMAT exam."

"The TTP course maximizes the efficiency of the time you spend studying. It will take time and effort but I could almost guarantee that if you complete the course exactly as it is laid out you will get an amazing score. They also have a very responsive team willing to help with any questions you might have."

"TTP has two things that I think no other test prep company offers: A teaching approach that reinforces understanding and an attitude that will give you the mental preparedness needed to succeed on the test. TTP gives you a deep understanding of the concept you need to know while teaching you how to think."

Write a Review