document.write( "Question 23027: Jake can complete a job in 5 hours while Jerry can complete the same job in 3 hours. How long would it take to complete the job if Jake starts the job 2 hours before Jerry joins him? \n" ); document.write( "
Algebra.Com's Answer #11433 by deepikabansal(5)\"\" \"About 
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Solution: As given in problem
\n" ); document.write( " In 5 hours Jake can do 1 job
\n" ); document.write( " =>In 1 hour he can do 1/5 job
\n" ); document.write( " similarly
\n" ); document.write( " in 3 hours Jerry can do 1 job
\n" ); document.write( " => in 1 hour she can do 1/3 job
\n" ); document.write( " so together in 1 hour they can do (1/5) +(1/3)job
\n" ); document.write( " =(3+5)/15job
\n" ); document.write( " =8/15job Now, jack has done 2 hours job alone before she joins him.
\n" ); document.write( "so job done by jack alone=2/5job
\n" ); document.write( "job remaining=1-(2/5)=3/5
\n" ); document.write( "this 3/5job has to be done by both of them
\n" ); document.write( "by unitary method,
\n" ); document.write( "as 8/15 job is done in 1 hour\r
\n" ); document.write( "\n" ); document.write( " 1 job is done in 15/8 hours
\n" ); document.write( " 3/5 job is done in (15/8)*(3/5)hours
\n" ); document.write( " 9/8 hours
\n" ); document.write( " ie 1hour7.5minutes.
\n" ); document.write( "so they will complete job in 1hour and 7.5 minutes \n" ); document.write( "
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