document.write( "Question 455228: Hello, I need help with this problem:\r
\n" ); document.write( "\n" ); document.write( "The intensity of a light source varies inversely with the square of the distance from the source. Four feet from the source the intensity is 9 foot candles. What is the intensity 3 feet from the source.\r
\n" ); document.write( "\n" ); document.write( "Thank you. \n" ); document.write( "
Algebra.Com's Answer #312546 by stanbon(75887)\"\" \"About 
You can put this solution on YOUR website!
The intensity of a light source varies inversely with the square of the distance from the source.
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\n" ); document.write( "I = k/d^2
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\n" ); document.write( "Solve for \"k\" using \"Four feet from the source the intensity is 9 foot candles\".
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\n" ); document.write( "9 = k/4^2
\n" ); document.write( "k = 9*16 = 144
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\n" ); document.write( "Equation:
\n" ); document.write( "I = 144/d^2
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\n" ); document.write( "What is the intensity 3 feet from the source.
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\n" ); document.write( "I = 144/3^2
\n" ); document.write( "I = 16 ft. candles
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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