document.write( "Question 493040: if it takes person A 7 hours to do something, and person b 12 hours to do the same thing, how long would it take in minutes if they worked together? \n" ); document.write( "

Algebra.Com's Answer #335261 by josmiceli(19441) $\"\"$ $\"About$

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Add their rates of working
\n" ); document.write( "In words:
\n" ); document.write( "A's rate is
\n" ); document.write( "( 1 job ) / ( 7 hours )
\n" ); document.write( "B's rate is
\n" ); document.write( "( 1 job ) / 12 hours )
\n" ); document.write( "Add their rates and make the sum
\n" ); document.write( "equal to ( 1 job ) / ( x hours )
\n" ); document.write( " $\"+1%2F7+%2B+1%2F12+=+1%2Fx+\"$
\n" ); document.write( "Multiply both sides by $\"+84x+\"$
\n" ); document.write( " $\"+12x+%2B+7x+=+84+\"$
\n" ); document.write( " $\"+19x+=+84+\"$
\n" ); document.write( " $\"+x+=+4.421+\"$ hours
\n" ); document.write( " $\"+4.421%2A60+=+265.26+\"$ minutes
\n" ); document.write( " $\"+.26%2A60+=+16+\"$ seconds
\n" ); document.write( "It will take them 265 minutes and 16 seconds
\n" ); document.write( "check answer:
\n" ); document.write( " $\"+1%2F7+=+.14286+\"$
\n" ); document.write( " $\"+1%2F12+=+.08333+\"$
\n" ); document.write( " $\"+.14286+%2B+.08333+=+.2262+\"$
\n" ); document.write( "and
\n" ); document.write( " $\"+1%2F4.421+=+.2262+\"$
\n" ); document.write( "OK \n" ); document.write( "

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