document.write( "Question 380315: Please help me solve:\r
\n" ); document.write( "\n" ); document.write( "If Sally can paint a house in 4 hours, and John can paint the same house in 6 hours, how long will it take for both of them to paint the house together?\r
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Algebra.Com's Answer #269899 by ewatrrr(24785) $\"\"$ $\"About$

You can put this solution on YOUR website!


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document.write( "Hi,
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document.write( " Sally can paint a house in 4 hrs, and John can paint the same house in 6 hrs
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document.write( "Let x represent the time it takes them together.  Per hour the Equalizer
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document.write( " 1/4 + 1/ 6 = 1/x  Mulitplying each term by 12x so as all denominators = 1
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document.write( " 3x + 2x = 12
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document.write( "    5x = 12
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document.write( "     x = 12/5  Or 2.4 hrs, the time it takes them together (2hr & 24min)\r
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document.write( "Note: the time painting the house together is always considerably less than
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document.write( "the time it takes one of them to do it alone. In this case Sally can paint the
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document.write( "house ALONE in 4 hrs..an answer of 3hrs and 12 min Together...NO 
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document.write( "that would mean John would take 16hr to paint the house alone ..
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document.write( "1/4 + 1/16 = 1/x , 4x + x = 16, 5x = 16, x = 3.2  Or 3hrs and 12 min. \n" );
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