document.write( "Question 132052: It takes Gary 1 hour to milk all the cows, and it takes Dana 1.5 hours. How long will it take them to do the job together? Please explain all the steps and models/equations used. Thanks so much. \n" ); document.write( "
Algebra.Com's Answer #96432 by ptaylor(2198)\"\" \"About 
You can put this solution on YOUR website!
Let x=amount of time it takes Dana and Gary working together to milk all the cows.
\n" ); document.write( "To start with, lets work in minutes on this problem:\r
\n" ); document.write( "\n" ); document.write( "Gary can milk 1/60 of the cows per minute
\n" ); document.write( "Dana can milk 1/90 of the cows per minute\r
\n" ); document.write( "\n" ); document.write( "Together, they can milk 1/60 + 1/90 of the cows per minute which equals
\n" ); document.write( "3/180+2/180 = 5/180=1/36 of the cows per minute\r
\n" ); document.write( "\n" ); document.write( "So our equation to solve is:\r
\n" ); document.write( "\n" ); document.write( "(1/36)*x=1(1 being one job or all the cows) multiply both sides by 36\r
\n" ); document.write( "\n" ); document.write( "x=36 min---------------time it takes Dana and Gary working together to milk all the cows.\r
\n" ); document.write( "\n" ); document.write( "Now, we will go ahead and solve it without switching to minutes\r
\n" ); document.write( "\n" ); document.write( "Gary milks at the rate of all the cows (or 1 job) per hour
\n" ); document.write( "Dana milks at the rate of 1/1.5 or 2/3 of the cows (2/3 job) per hour\r
\n" ); document.write( "\n" ); document.write( "Together they milk at the rate of 1 +2/3 of the cows per hour or\r
\n" ); document.write( "\n" ); document.write( "3/3+2/3=5/3 of the cows per hour so our equation to solve is (Note: this tells us that working together, they can milk more that all the cows per hour):\r
\n" ); document.write( "\n" ); document.write( "(5/3)*x=1(1 being one job or all the cows) multiply each side by 3\r
\n" ); document.write( "\n" ); document.write( "5x=3 divide both sides by 5
\n" ); document.write( "x=3/5---- hour time it takes Dana and Gary working together to milk all the cows.
\n" ); document.write( "(note that 3/5 hr =(3/5)*60=36 min)\r
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\n" ); document.write( "\n" ); document.write( "Hope this helps----ptaylor\r
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