document.write( "Question 72978: My question: Could you show me the formula to use to answer the question below?\r
\n" ); document.write( "\n" ); document.write( "Math Question: I have 2 candles with equal lengths. Both candles are lit at the same time. Candle A burns out at 9 hours. Candle B burns out at 6 hours. At what time is the slower burning candle twice as long as the faster burning candle?\r
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Algebra.Com's Answer #52201 by ankor@dixie-net.com(22740)\"\" \"About 
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2 candles with equal lengths. Both candles are lit at the same time. Candle A burns out at 9 hours. Candle B burns out at 6 hours. At what time is the slower burning candle twice as long as the faster burning candle?
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\n" ); document.write( "For convenience let's assign a length of 9\" to the candles
\n" ); document.write( "That means:
\n" ); document.write( "Candle A burns 1\"/hr and candle B burns 1.5\"/hr
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\n" ); document.write( "Let t = hrs until A is twice as long as B
\n" ); document.write( "An equation:
\n" ); document.write( "9 - 1t = 2(9 - 1.5t)
\n" ); document.write( "9 - t = 18 - 3t
\n" ); document.write( "-t + 3t = 18 - 9
\n" ); document.write( "2t = 9
\n" ); document.write( "t = 4.5 hrs
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\n" ); document.write( "Check:
\n" ); document.write( " candle A after 4.5 hrs: 9 - (4.5 * 1) = 4.5\"
\n" ); document.write( " candle B after 4.5 hrs: 9 - (4.5 * 1.5) = 9 - 6.75 = 2.25\"
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