document.write( "Question 967061: Pete can do a job in 4 hours less than Sam can. Working together,they can complete the job in 16 hours. How long would it take each working alone? Round your answer to the nearest tenth of an hour \n" ); document.write( "

Algebra.Com's Answer #591050 by josmiceli(19441) $\"\"$ $\"About$

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Add their rates of working
\n" ); document.write( "Let $\"+t+\"$ = time it takes Sam to do job
\n" ); document.write( "[ 1 job ] / [ t hrs ] = rate for Sam
\n" ); document.write( "[ 1 job ] / [ t - 4 hrs ] = rate for Pete
\n" ); document.write( "[ 1 job ] / [ 16 hrs ] = their rate working together
\n" ); document.write( "----------------------
\n" ); document.write( " $\"+1%2Ft+%2B+1%2F%28+t-4+%29+=+1%2F16+\"$
\n" ); document.write( "Multiply both sides by $\"+t%2A%28+t-4+%29%2A16+\"$
\n" ); document.write( " $\"+16%2A%28+t-4+%29+%2B+16t+=+t%2A%28+t-4+%29+\"$
\n" ); document.write( " $\"+16t+-+64+%2B+16t+=+t%5E2+-+4t+\"$
\n" ); document.write( " $\"+t%5E2+-+36t+%2B+64+=+0+\"$
\n" ); document.write( "Use quadratic formula
\n" ); document.write( " $\"+t+=+%28+-b+%2B-+sqrt%28+b%5E2+-+4%2Aa%2Ac+%29%29+%2F+%282%2Aa%29+\"$
\n" ); document.write( " $\"+a+=+1+\"$
\n" ); document.write( " $\"+b+=+-36+\"$
\n" ); document.write( " $\"+c+=+64+\"$
\n" ); document.write( "You can finish. Find $\"+t+\"$
\n" ); document.write( "and $\"+t+%2B+4+\"$ \r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

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