document.write( "Question 668250: Jacob can complete a plant installation in 5 hours using a planting tool. Aiden can complete the same plant installation in 20 hours using conventional tools. How long would it take the two men together to complete the plant installation if they are working together, each working with his tools? \n" ); document.write( "
Algebra.Com's Answer #415412 by stanbon(75887)\"\" \"About 
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Jacob can complete a plant installation in 5 hours using a planting tool. Aiden can complete the same plant installation in 20 hours using conventional tools. How long would it take the two men together to complete the plant installation if they are working together, each working with his tools?
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\n" ); document.write( "Jacob's rate: 1/5 job/hr
\n" ); document.write( "Alden's rate: 1/20 job/hr
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\n" ); document.write( "Together rate: 1/x job/hr
\n" ); document.write( "Equation:
\n" ); document.write( "rate + rate = together rate
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\n" ); document.write( "1/5 + 1/20 = 1/x
\n" ); document.write( "4x + x = 20
\n" ); document.write( "5x = 20
\n" ); document.write( "x = 4 hrs (time for them to do the job together)
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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