Geometry question

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Geometry question

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]
Source: — Problem Solving |

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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

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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

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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 ????