Difference between revisions of "2005 Alabama ARML TST Problems/Problem 2"

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==Solution==
 
==Solution==
The cube is <math>4\times 4\times4</math>. Only the inside sub-cubes are unpainted, thus all but <math>8</math> are unpainted, leaving <math>64-8=56 </math>painted.
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The cube is <math>4\times 4\times4</math>. Only the inside sub-cubes are unpainted, thus <math>8</math> are unpainted, leaving <math>64-8=56</math> painted.
  
 
==See also==
 
==See also==

Latest revision as of 12:06, 26 January 2009

Problem

A large cube is painted green and then chopped up into 64 smaller congruent cubes. How many of the smaller cubes have at least one face painted green?

Solution

The cube is $4\times 4\times4$. Only the inside sub-cubes are unpainted, thus $8$ are unpainted, leaving $64-8=56$ painted.

See also

2005 Alabama ARML TST (Problems)
Preceded by:
Problem 1
Followed by:
Problem 3
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