document.write( "Question 943734: Sarah can paint a fence in 4 hours. Her father Joe can paint it in 2 hours. If they work together, how long will it take them? \n" ); document.write( "

Algebra.Com's Answer #575393 by ptaylor(2198) $\"\"$ $\"About$

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Let x=amt of time it takes Sarah and her father working together to paint the fence
\n" ); document.write( "Then Sarah and her father working together paints at the rate of 1/x of the fence per hour
\n" ); document.write( "Sarah paints at the rate of 1/4 of the fence per hour
\n" ); document.write( "Her father paints at the rate of 1/2 of the fence per hour
\n" ); document.write( "Sooooo
\n" ); document.write( "1/4 + 1/2 = 1/x multiply each term by 4x
\n" ); document.write( "x + 2x=4
\n" ); document.write( "3x=4
\n" ); document.write( "x=4/3 hr= 1 hr 20 min
\n" ); document.write( "CK
\n" ); document.write( "(4/3)(1/4)+(4/3)(1/2) should equal 1 (1 fence, that is)
\n" ); document.write( "(1/3) +(2/3)=1
\n" ); document.write( "1=1
\n" ); document.write( "Hope this helps--- ptaylor \n" ); document.write( "

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