document.write( "Question 818401: Pat and Jane want to paint a fence, pat can paint the fence by himself in 3 hours, jane can paint the fence by herself in 4 hours. At noon, they start painting the fence together. At some point, they argue for ten minutes, and no painting gets done. After the arguement, jane leaves and pat paints alone. If pat finishes painting at 2:25 pm, at what time did the argument begin? How do u solve.....is it a work rate problem? \n" ); document.write( "
Algebra.Com's Answer #492550 by josmiceli(19441)\"\" \"About 
You can put this solution on YOUR website!
it's a work problem that is divided
\n" ); document.write( "into 3 parts:
\n" ); document.write( "(1) painting done by both
\n" ); document.write( "(2) short period of no painting
\n" ); document.write( "(3) painting done by Pat alone
\n" ); document.write( "------------------------
\n" ); document.write( "Let \"+t%5B1%5D+\" = the amount of time in hours
\n" ); document.write( "from noon to when they started their
\n" ); document.write( "10 minute argument
\n" ); document.write( "-----------------
\n" ); document.write( "Let \"+t%5B2%5D+\" = the amount of time in hours
\n" ); document.write( "from the end of the 10 minute argument
\n" ); document.write( "to 2:25 PM
\n" ); document.write( "---------
\n" ); document.write( "Let \"+x+\" = the fraction of the job that they
\n" ); document.write( "both get done in the 1st time period
\n" ); document.write( "----------------------------
\n" ); document.write( "\"+1+-+x+\" = the fraction of the job that
\n" ); document.write( "Pat does in the 3rd time period
\n" ); document.write( "-------------------------
\n" ); document.write( "-------------------------
\n" ); document.write( "For the 1st time period, I can say:
\n" ); document.write( "\"+1%2F3+%2B+1%2F4+=+x%2Ft%5B1%5D+\"
\n" ); document.write( "Multiply both sides by \"+12+\"
\n" ); document.write( "\"+4+%2B+3+=+12%2A%28+x%2Ft%5B1%5D%29+\"
\n" ); document.write( "\"+x%2Ft%5B1%5D+=+7%2F12+\"
\n" ); document.write( "(a) \"+t%5B1%5D+=+%2812%2F7%29%2Ax+\"
\n" ); document.write( "----------------
\n" ); document.write( "Fot the 3rd time period:
\n" ); document.write( "\"+1%2F4+=+%28+1-x+%29+%2F+t%5B2%5D+\"
\n" ); document.write( "Multiply both sides by \"+4%2At%5B2%5D+\"
\n" ); document.write( "\"+t%5B2%5D+=+4%2A%28+1-x+%29+\"
\n" ); document.write( "(b) \"+t%5B2%5D+=+4+-+4x+\"
\n" ); document.write( "-----------------
\n" ); document.write( "So far I have 2 equations and 3 unknowns.
\n" ); document.write( "The 3rd equation is:
\n" ); document.write( "\"+t%5B1%5D+%2B+1%2F6+%2B+t%5B2%5D+=+2+%2B+5%2F12+\"
\n" ); document.write( "( note that I converted minutes to hours )
\n" ); document.write( "\"+t%5B1%5D+%2B+t%5B2%5D+=+2+%2B+5%2F12+-+2%2F12++\"
\n" ); document.write( "(c) \"+t%5B1%5D+%2B+t%5B2%5D+=+27%2F12+\"
\n" ); document.write( "Substitute (a) and (b) into (c)
\n" ); document.write( "(c) \"+%2812%2F7%29%2Ax+%2B+4+-+4x+=+9%2F4+\"
\n" ); document.write( "Multiply both sides by \"+28+\"
\n" ); document.write( "(c) \"+48x+%2B+112+-+112x+=+63+\"
\n" ); document.write( "(c) \"+64x+=+112+-+63+\"
\n" ); document.write( "(c) \"+64x+=+49+\"
\n" ); document.write( "(c) \"+x+=+49%2F64+\"
\n" ); document.write( "---------------
\n" ); document.write( "(a) \"+t%5B1%5D+=+%2812%2F7%29%2Ax+\"
\n" ); document.write( "(a) \"+t%5B1%5D+=+%2812%2F7%29%2A%2849%2F64%29+\"
\n" ); document.write( "(a) \"+t%5B1%5D+=+84%2F64+\"
\n" ); document.write( "(a) \"+t%5B1%5D+=+21%2F16+\"
\n" ); document.write( "and
\n" ); document.write( "(b) \"+t%5B2%5D+=+4+-+4x+\"
\n" ); document.write( "(b) \"+t%5B2%5D+=+4+-+4%2A%2849%2F64%29+\"
\n" ); document.write( "(b) \"+t%5B2%5D+=+4%2A%28+1+-+49%2F64+%29+\"
\n" ); document.write( "(b) \"+t%5B2%5D+=+4%2A%28+15%2F64+%29+\"
\n" ); document.write( "(b) \"+t%5B2%5D+=+15%2F16+\"
\n" ); document.write( "------------------
\n" ); document.write( "check:
\n" ); document.write( "\"+t%5B1%5D+%2B+1%2F6+%2B+t%5B2%5D+=+2+%2B+5%2F12+\"
\n" ); document.write( "\"+21%2F16+%2B+1%2F6+%2B+15%2F16+=+2+%2B+5%2F12+\"
\n" ); document.write( "\"+36%2F16+=+2+%2B+5%2F12+-+2%2F12+\"
\n" ); document.write( "\"+36%2F16+=+27%2F12+\"
\n" ); document.write( "\"+9%2F4+=+9%2F4+\"
\n" ); document.write( "OK
\n" ); document.write( "-------
\n" ); document.write( "Noon plus \"+t%5B1%5D+\" = \"+21%2F16+\"
\n" ); document.write( "\"+21%2F16+=+16%2F16+%2B+5%2F16+\"
\n" ); document.write( "\"+%285%2F16%29%2A60+=+18.75+\"
\n" ); document.write( "\"+.75%2A60+=+45+\"
\n" ); document.write( "The argument began at 1:18:45
\n" ); document.write( "Unless I made a mistake- check the work
\n" ); document.write( "
\n" ); document.write( "
\n" );