document.write( "Question 786580: Pat and Jen volunteer at the library. Pat can shelve a full cart of books 12 minutes faster than Jen. If they work together, they can shelve a full cart in 100 minutes. How log does it take Jen to shelve a full cart by herself? (Give an exact answer rounded to the nearest minute)\r
\n" ); document.write( "\n" ); document.write( "I tried making a table where p is the value of pats time represented as \"x\" and j is the value of jens time represented as \"x+12\". I made a table that I would normally use for these kinds of promlems but I keep getting an odd number and I cant seem to figure it out
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Algebra.Com's Answer #477913 by josmiceli(19441)\"\" \"About 
You can put this solution on YOUR website!
I don't use tables, but my equations can
\n" ); document.write( "easily be put into a table
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\n" ); document.write( "Add their rates to get rate working together
\n" ); document.write( "Jen's rate: ( 1 cart ) / ( x min )
\n" ); document.write( "Pat's rate: ( 1 cart ) / ( x - 12 min )
\n" ); document.write( "Together: ( 1 cart ) / ( 100 min )
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\n" ); document.write( "\"+1%2Fx+%2B+1%2F%28+x-12+%29+=+1%2F100+\"
\n" ); document.write( "Multiply both sides by \"+x%2A%28+x-12+%29%2A100+\"
\n" ); document.write( "\"+100%2A%28x-12%29+%2B+x%2A100+=+x%2A%28+x-12+%29+\"
\n" ); document.write( "\"+100x+-+1200+%2B+100x+=+x%5E2+-+12x+\"
\n" ); document.write( "\"+x%5E2+-+212x+%2B+1200+=+0+\"
\n" ); document.write( "Use quadratic formula
\n" ); document.write( "\"+x+=+%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+=+-212+\"
\n" ); document.write( "\"+c+=+1200+\"
\n" ); document.write( "\"+x+=+%28+-%28-212%29+%2B-+sqrt%28+%28-212%29%5E2-4%2A1%2A1200+%29%29+%2F+%282%2A1%29+\"
\n" ); document.write( "\"+x+=+%28+212+%2B-+sqrt%28+44944+-4800+%29%29+%2F+2+\"
\n" ); document.write( "\"+x+=+%28+212+%2B-+sqrt%28+40144+%29%29+%2F+2+\"
\n" ); document.write( "\"+x+=+%28+212+%2B+200.36+%29+%2F+2+\"
\n" ); document.write( "\"+x+=+412.36%2F2+\"
\n" ); document.write( "\"+x+=+206.18+\"
\n" ); document.write( "In hours:
\n" ); document.write( "\"+206.18+%2F+60+=+3+%2B+26.18%2F60+\"
\n" ); document.write( "It would take Jen 3 hrs and 26 min
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\n" ); document.write( "check:
\n" ); document.write( "\"+x+-+12+=+206.18+-+12+\"
\n" ); document.write( "\"+x+-+12+=+194.18+\"
\n" ); document.write( "\"+1%2Fx+%2B+1%2F%28+x-12+%29+=+1%2F100+\"
\n" ); document.write( "\"+1%2F206.18+%2B+1%2F194.18+=+1%2F100+\"
\n" ); document.write( "\"+.00485+%2B+.00515+=+.01+\"
\n" ); document.write( "\"+.01+=+.01+\"
\n" ); document.write( "OK\r
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