document.write( "Question 602969: It takes Nina 3 hours to proof a chapter of Hawkes Learning Systems' Statistics book and it takes Cynthia 12 hours. How long would it take them together? \n" ); document.write( "

Algebra.Com's Answer #380508 by ewatrrr(24785) $\"\"$ $\"About$

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document.write( "Hi,
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document.write( "It takes Nina 3 hours to proof a chapter of Hawkes Learning Systems' Statistics
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document.write( " book and it takes Cynthia 12 hours.
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document.write( "Let x represent the time it would take them together
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document.write( "Note: job / hour is the key
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document.write( " 1/3 + 1/12 = 1/x       |Multiplying thru by 12x so as all denominators = 1
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document.write( "4x + x = 12
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document.write( "   5x = 12
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document.write( "    x = 2.4 hrs, the time it would take them together \n" );
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