document.write( "Question 331949: A wooden cube whose edges are 4 inches is painted green.The cube is then cut into
\n" ); document.write( "64 one-inch cubes. How many small cubes have exactly 1 green face?
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Algebra.Com's Answer #237937 by galactus(183)\"\" \"About 
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The number of one side paintings on an nxnxn cube is \r
\n" ); document.write( "\n" ); document.write( "\"6%28n-2%29%5E2\"\r
\n" ); document.write( "\n" ); document.write( "In this case, we are told that n=4. So we have:\r
\n" ); document.write( "\n" ); document.write( "\"6%284-2%29%5E2=24\"\r
\n" ); document.write( "\n" ); document.write( "There are 24 little cubies with only one side painted.\r
\n" ); document.write( "\n" ); document.write( "The number with two sides painted is \"12%28n-2%29\"\r
\n" ); document.write( "\n" ); document.write( "\"12%284-2%29=24\"\r
\n" ); document.write( "\n" ); document.write( "The number with three sides painted is always 8. They are on the corners and that is true regardless of the cube size. \r
\n" ); document.write( "\n" ); document.write( "Those remaining are the ones in the center with no paint. That is\r
\n" ); document.write( "\n" ); document.write( "\"%28n-2%29%5E3\"\r
\n" ); document.write( "\n" ); document.write( "\"%284-2%29%5E3=8\"\r
\n" ); document.write( "\n" ); document.write( "So, we have 24+24+8+8=64...as it should be.\r
\n" ); document.write( "\n" ); document.write( "Add up the formulas:\r
\n" ); document.write( "\n" ); document.write( "\"8%2B%28n-2%29%5E3%2B6%28n-2%29%5E2%2B12%28n-2%29\"\r
\n" ); document.write( "\n" ); document.write( "A pattern. A binomial. Add these up and it reduces all the way down to\r
\n" ); document.write( "\n" ); document.write( "\"n%5E3\"\r
\n" ); document.write( "\n" ); document.write( "Just as we expected. 4^3=64\r
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