document.write( "Question 434896: Two contractors were working together to finish concrete. One can finish 25 sqaure yards in 4 hours, and the other can finish 25 sqaure yards in 5 hours. How much concrete can they finish in 8 hours working together? \n" ); document.write( "
Algebra.Com's Answer #312851 by jorel1380(3719)\"\" \"About 
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1/4+1/5=1/t
\n" ); document.write( "5/20+4/20=9/20=1/t
\n" ); document.write( "9t=20
\n" ); document.write( "t=20/9
\n" ); document.write( "The two contractors can finish 25 square yards in 20/9 hours
\n" ); document.write( "8/(20/9)=72/20=3.6
\n" ); document.write( "3.6x25=90 sq. yds..
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