document.write( "Question 613378: One robot can vacuum a house in 10 hours. If a second robot is added and both are used, the same job can be completed in 3 hours. How long would it take the second robot alone to do the same job? \n" ); document.write( "

Algebra.Com's Answer #386029 by ewatrrr(24785) $\"\"$ $\"About$

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document.write( "Hi, 
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document.write( "One robot can vacuum a house in 10 hours. If a second robot is added and both
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document.write( " are used, the same job can be completed in 3 hours
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document.write( "Let x represent the time the second robot would take alone:
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document.write( "PER hour KEY:
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document.write( " 1/10 + 1/x = 1/3 ||Multiplying thru by 30x so as all denominators = 1
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document.write( " 3x + 30 = 10x
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document.write( "     30 = 7x
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document.write( "     4 2/7 hr = x, the time the second robot would take alone \n" );
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