document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=451511>Question 451511</A>: <I><SPAN STYLE=\"word-break: break-all;\"> One printing press can print the first edition of a book in 28 min, whereas a second printing press requires 70 min to print the same number of copies. How long would it take to print the first edition with both presses operating? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #310468 by </B><A HREF=/tutors/aboutme.mpl?userid=pedjajov><B>pedjajov(51)</B></A><img src=\"/images/stars/stars-08.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=pedjajov><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=310468\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> First press prints <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F28 ALIGN=MIDDLE  ALT=\"1%2F28\"   DISABLED_style= \"max-width:90%; height:auto;\" > of the book in a minute while the second press does <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F70 ALIGN=MIDDLE  ALT=\"1%2F70\"   DISABLED_style= \"max-width:90%; height:auto;\" > of the book in a minute.\r<BR>\n" );
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document.write( "Working together they will print\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F28+%2B+1%2F70 ALIGN=MIDDLE  ALT=\"1%2F28+%2B+1%2F70\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=5%2F140+%2B+2%2F140 ALIGN=MIDDLE  ALT=\"5%2F140+%2B+2%2F140\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=7%2F140 ALIGN=MIDDLE  ALT=\"7%2F140\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F20 ALIGN=MIDDLE  ALT=\"1%2F20\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Now we can make a proportion that <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F20 ALIGN=MIDDLE  ALT=\"1%2F20\"   DISABLED_style= \"max-width:90%; height:auto;\" > of the book both presses print in a minute and we want to find out how long it takes both presses to print one book:\r<BR>\n" );
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document.write( "1/20 book : 1 minutes = 1 book : x minutes\r<BR>\n" );
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document.write( "1/20 * x = 1 * 1\r<BR>\n" );
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document.write( "x = 1 * 1 / (1/20)\r<BR>\n" );
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document.write( "x = 20 minutes </SPAN>\n" );
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