document.write( "Question 948826: A and B can do a work in 12 days and 20 days.A works alone for 4 days and then B joins to help.in how many days will they finish the job?\r
\n" ); document.write( "\n" ); document.write( "ans- A in 1 day = 1/12
\n" ); document.write( " B in 1 day = 1/20
\n" ); document.write( "A alone works for 4 days
\n" ); document.write( "therefore in 4 days A'work = 4*1/20= 1/5
\n" ); document.write( "Remaining work 4/5
\n" ); document.write( "then B joins......
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Algebra.Com's Answer #579236 by Fombitz(32388)\"\" \"About 
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\n" ); document.write( "A working for 4 days would be,
\n" ); document.write( "\"A%2A4=%281%2F12%294=1%2F3\"
\n" ); document.write( "So that leaves \"2%2F3\" to complete.
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\n" ); document.write( "So then use the rate for A and B together.
\n" ); document.write( "\"A%2BB=1%2F12%2B1%2F20=5%2F60%2B3%2F60=8%2F60=2%2F15\"
\n" ); document.write( "So then,
\n" ); document.write( "\"%28A%2BB%29t=2%2F3\"
\n" ); document.write( "\"%282%2F15%29t=2%2F3\"
\n" ); document.write( "\"t=5\" \"days\"\r
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