document.write( "Question 365335: After Hurricane Bob, the Duvals needed to remove water from thier flooded basement. They had a sump pump and borrowed a second from a local fire department. The chief explained that he expects both pumps working together will empty the basement in 6 hours. The fire dept. sump pump has a higher horsepower and would empty the basement itself in 2 hours less time than the Duval's pump alone. how long would it take each pump to empty the cellar if each were working alone? \n" ); document.write( "
Algebra.Com's Answer #260440 by stanbon(75887)![]() ![]() ![]() You can put this solution on YOUR website! The chief explained that he expects both pumps working together will empty the basement in 6 hours. The fire dept. sump pump has a higher horsepower and would empty the basement itself in 2 hours less time than the Duval's pump alone. how long would it take each pump to empty the cellar if each were working alone? \n" ); document.write( "---- \n" ); document.write( "together rate = 1/6 job/hr \n" ); document.write( "fire dept rate : 1/(x-2) job/hr \n" ); document.write( "Duval pump rate: 1/x job/hr \n" ); document.write( "------ \n" ); document.write( "Equation: \n" ); document.write( "rate + rate = together rate \n" ); document.write( "1/x + 1/(x-2) = 1/6 \n" ); document.write( "6(x-2) + 6x = x(x-2) \n" ); document.write( "6x-12 + 6x = x^2-2x \n" ); document.write( "x^2 -14x + 12 = 0 \n" ); document.write( "Positive solution: \n" ); document.write( "x = 13.08 (Duval pump rate) \n" ); document.write( "x-2 = 11.08 hrs. (fire dept rate) \n" ); document.write( "------------- \n" ); document.write( "Cheers, \n" ); document.write( "Stan H. \n" ); document.write( " \n" ); document.write( " |