document.write( "Question 1036417: David can do a job in 15 days while ken can do the same job in 10 days.If both started the work together and ken quit after 2 days while david finished the job how long will the entire job take? \n" ); document.write( "

Algebra.Com's Answer #651068 by josmiceli(19441) $\"\"$ $\"About$

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David's rate of working:
\n" ); document.write( "[ 1 job ] / [ 15 days ]
\n" ); document.write( "Ken's rate of working:
\n" ); document.write( "[ 1 job ] / [ 10 days ]
\n" ); document.write( "---------------------
\n" ); document.write( "Add their rates of working to get their
\n" ); document.write( "rate working together
\n" ); document.write( " $\"+1%2F15+%2B+1%2F10+=+2%2F30+%2B+3%2F30+\"$
\n" ); document.write( " $\"+2%2F30+%2B+3%2F30+=+5%2F30+\"$
\n" ); document.write( " $\"+5%2F30+=+1%2F6+\"$
\n" ); document.write( "------------------
\n" ); document.write( "Their rate working together is:
\n" ); document.write( "[ 1 job ] / [ 6 days ]
\n" ); document.write( "------------------
\n" ); document.write( "In 2 days, the fraction of the job completed is
\n" ); document.write( " $\"+2%2A%28+1%2F6+%29+=+1%2F3+\"$
\n" ); document.write( "That means there is $\"+2%2F3+\"$ of the job left
\n" ); document.write( "after 2 days
\n" ); document.write( "-------------------------------------
\n" ); document.write( "Ken leaves after 2 days.
\n" ); document.write( "Let $\"+t+\"$ = time in days for David to finish the job
\n" ); document.write( " $\"+1%2F15+=+%28%28+2%2F3+%29%29+%2F+t+\"$
\n" ); document.write( " $\"+1%2F15+=+2%2F%28+3t+%29+\"$
\n" ); document.write( "Multiply both sides by $\"+15t+\"$
\n" ); document.write( " $\"+t+=+10+\"$
\n" ); document.write( "David takes 10 days to finish the job
\n" ); document.write( " $\"+2+%2B+10+=+12+\"$
\n" ); document.write( "The entire job takes 12 days to finish \n" ); document.write( "

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