Difference between revisions of "2005 AMC 12B Problems/Problem 16"

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== Problem ==
 
== Problem ==
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Eight spheres of radius 1, one per octant, are each tangent to the coordinate planes. What is the radius of the smallest sphere, centered at the origin, that contains these eight spheres?
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<math>
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\mathrm (A)\ \sqrt{2}  \qquad
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\mathrm (B)\ \sqrt{3}  \qquad
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\mathrm (C)\ 1+\sqrt{2}\qquad
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\mathrm (D)\ 1+\sqrt{3}\qquad
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\mathrm (E)\ 3
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</math>
  
 
== Solution ==
 
== Solution ==

Revision as of 14:53, 23 February 2010

Problem

Eight spheres of radius 1, one per octant, are each tangent to the coordinate planes. What is the radius of the smallest sphere, centered at the origin, that contains these eight spheres?

$\mathrm (A)\ \sqrt{2}  \qquad \mathrm (B)\ \sqrt{3}  \qquad \mathrm (C)\ 1+\sqrt{2}\qquad \mathrm (D)\ 1+\sqrt{3}\qquad \mathrm (E)\ 3$

Solution

See also