document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=113478>Question 113478</A>: <I><SPAN STYLE=\"word-break: break-all;\"> can you help me?\r<BR>\n" );
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document.write( "1.an older computer unit requires 12min more to print a company's payroll than does a newer computer unit. used together the computers can print the payroll in 8 min. find the time the new computer unit, used alone, will require to print the payroll.\r<BR>\n" );
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document.write( "2.working together. Dan and Leah can mow a lawn in 1 h and 12 min. Working alone, Leah can mow the lawn in 1 h less time than it would take Dan. Find the time it takes for each of them, working on his/her own, to mow the lawn.\r<BR>\n" );
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document.write( "i hope you can help me..<BR>\n" );
document.write( "god bless..\r<BR>\n" );
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document.write( " </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #82545 by </B><A HREF=/tutors/aboutme.mpl?userid=moou_b><B>moou_b(3)</B></A><img src=\"/images/stars/iconNewId_16x16.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=moou_b><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=82545\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> ANSWER 1.\r<BR>\n" );
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document.write( "let the new comp. can print the whole payroll in 'x' min.<BR>\n" );
document.write( "therefore in 1 min. it will do 1/x of printing.<BR>\n" );
document.write( "the old comp. takes x+12 min. to do the whole printing.<BR>\n" );
document.write( "therefore in 1 min. it will do 1/x+12 of printing.<BR>\n" );
document.write( "together they do the printing in 8 min.<BR>\n" );
document.write( "therefore in 1 min. they do 1/8 of printing.<BR>\n" );
document.write( "now, (1/x) + (1/x+12) = 1/8<BR>\n" );
document.write( "     x+12+x/x(x+12)   = 1/8<BR>\n" );
document.write( "     2x+12/x(x+12)    = 1/8<BR>\n" );
document.write( "     16x+96           = x(x+12)<BR>\n" );
document.write( "     16x+96           = x^2+12x ( x to the power 2+12x)<BR>\n" );
document.write( "     x^2+12x-16x       = 96<BR>\n" );
document.write( "     x^2-4x-96         = 0<BR>\n" );
document.write( "     x^2-12x+8x-96     = 0<BR>\n" );
document.write( "     x(x-12)+8(x-12)  = 0<BR>\n" );
document.write( "     (x-12)+(x+8)     = 0<BR>\n" );
document.write( "when x-12 = 0, x=12   and when x+8 = 0, x=(-8) neglecting the negetive term x=12 is the valid answer. therefore, the new comp. will take 12 min. to print the payroll alone.\r<BR>\n" );
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document.write( "ANSWER 2.\r<BR>\n" );
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document.write( "let dan takes x hrs. to mow the whole lawn.<BR>\n" );
document.write( "in 1 hr he will mow 1/x of the lawn.<BR>\n" );
document.write( "leah mows the lawn in (x-1) hrs.<BR>\n" );
document.write( "in 1 hr he will mow 1/(x-1) of the lawn<BR>\n" );
document.write( "leah & dan together mow the lawn in 1 hr. 12 min = 1 and 1/5 hr = 6/5 hrs.<BR>\n" );
document.write( "in 1 hr they mow 1/ 6/5 = 5/6 of the lawn.<BR>\n" );
document.write( "now, forming equation, we have, (1/x)+(1/x-1)= 5/6<BR>\n" );
document.write( "                                x-1+x/x(x-1) = 5/6<BR>\n" );
document.write( "                                2x-1/x(x-1)  = 5/6<BR>\n" );
document.write( "                                12x-6        = 5x^2-5x<BR>\n" );
document.write( "                                5x^2-5x-12x+6= 0<BR>\n" );
document.write( "                                5x^2-17x+6   = 0<BR>\n" );
document.write( "                                5x^2-15x-2x+6=0<BR>\n" );
document.write( "                                5x(x-3)-2(x-3)=0<BR>\n" );
document.write( "                                (5x-2)(x-3)  = 0<BR>\n" );
document.write( "when 5x-2=0,x=2/5 and when x-3=0, x=3<BR>\n" );
document.write( "as 2/5 hr solution is not valid because 2/5 hr=24 min.<BR>\n" );
document.write( "so dan can mow the lawn in 3 hrs and leah will mow the lawn 3-1=2 hrs.\r<BR>\n" );
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document.write( "hope the solution is understood. </SPAN>\n" );
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