document.write( "Question 397946: it takes mang kaloy 3 hrs to plow his ricefield with his new tractor. using the old tractor it takes him 5 hrs. if his son helped him plow the ricefield how long will it take them to plow the ricefield using both tractors \n" ); document.write( "

Algebra.Com's Answer #282032 by ankor@dixie-net.com(22740) $\"\"$ $\"About$

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it takes mang kaloy 3 hrs to plow his ricefield with his new tractor.
\n" ); document.write( " using the old tractor it takes him 5 hrs.
\n" ); document.write( " if his son helped him plow the ricefield how long will it take them to plow the ricefield using both tractors
\n" ); document.write( ":
\n" ); document.write( "Let t = time required working together
\n" ); document.write( "Let the completed job = 1 (a plowed rice field)
\n" ); document.write( ":
\n" ); document.write( " $\"t%2F5\"$ + $\"t%2F3\"$ = 1
\n" ); document.write( "multiply thru by 15, results
\n" ); document.write( "3t + 5t = 15
\n" ); document.write( "8t = 15
\n" ); document.write( "t = $\"15%2F8\"$
\n" ); document.write( "t = 1.875 hrs, or 1 + .875(60) = 1 hr 52.5 min \n" ); document.write( "

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