document.write( "Question 178779: Two cranes, operating together, can unload a cargo ship in 4 hours. If it takes one crane twice as long as the other to unload the ship, how long would it take each crane to unload the ship by itself? \n" ); document.write( "

Algebra.Com's Answer #133751 by Mathtut(3670) $\"\"$ $\"About$

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let y and x be the time crane 1 and crane 2, respectively, take to unload the ship by themselves. y=2x
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\n" ); document.write( "crane 1 does 1/2x of the job per hour
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\n" ); document.write( "crane 2 does 1/x of the job per hour
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\n" ); document.write( "(1/x+1/2x)(4)=1job
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\n" ); document.write( "((2+1)/2x)4=1
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\n" ); document.write( "12/2x=1
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\n" ); document.write( "2x=12=
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\n" ); document.write( " $\"highlight%28x=6%29\"$ hours-time for crane 2 to do the job
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\n" ); document.write( "y=2x $\"highlight%28%282%29%286%29=12%29\"$ hours-time for crane 1 to do the job \n" ); document.write( "

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