document.write( "Question 951015: if three machines can complete a job in 8 hours, 5 hours, and 4 hours respectively, when they work alone, how long will it take the three working together to complete the job \n" ); document.write( "

Algebra.Com's Answer #580713 by josgarithmetic(39618) $\"\"$ $\"About$

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The three are working together, meaning all three at the same time, meaning THE SUM OF THEIR RATES. The unit must be JOBS per HOUR. \n" ); document.write( "

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