document.write( "Question 774918: Jan can deliver the mail in 4 hours. It takes Marcia 6 hours to complete the same route. How long would it take to deliver the mail if they worked together? \n" ); document.write( "

Algebra.Com's Answer #472564 by josmiceli(19441) $\"\"$ $\"About$

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Jan's rate of delivering main:
\n" ); document.write( "( 1 mail route ) / ( 4 hrs )
\n" ); document.write( "Marcia's rate of delivering mail:
\n" ); document.write( "( 1 mail route ) / ( 6 hrs )
\n" ); document.write( "---------------------
\n" ); document.write( "Add their rates to ge rate working together
\n" ); document.write( "Let $\"+t+\"$ = time in hrs working togther
\n" ); document.write( " $\"+1%2F4+%2B+1%2F6+=+1%2Ft+\"$
\n" ); document.write( "Multiply both sides by $\"+12t+%7D%7D%0D%0A%7B%7B%7B+3t+%2B+2t++=+12+\"$
\n" ); document.write( " $\"+5t+=+12+\"$
\n" ); document.write( " $\"+t+=+12%2F5+=+2.4+\"$ hrs
\n" ); document.write( " $\"+.4%2A60+=+24+\"$
\n" ); document.write( "Working together, it will take them
\n" ); document.write( "2 hrs and 24 min\r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

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