document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=263393>Question 263393</A>: <I><SPAN STYLE=\"word-break: break-all;\"> An 8 hp pump can fill a tank in 8 hours. A smaller 3 hp pump fills the same tank in 12 hours. The pumps are used together to begin filling this tank. After four hours, the 8 hp pump breaks down. How long will it take the smaller pump to fill the tank? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #194114 by </B><A HREF=/tutors/aboutme.mpl?userid=drk><B>drk(1908)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=drk><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=194114\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> This is a working together problem.<BR>\n" );
document.write( "The rate of the 8 hp pump = 1/8<BR>\n" );
document.write( "the rate of the 3 hp pump is 1/12<BR>\n" );
document.write( "The time together will be 4 hours.<BR>\n" );
document.write( "The time that the 3 hp pump works alone is x hrs.<BR>\n" );
document.write( "We want to fill only 1 tank<BR>\n" );
document.write( "-----<BR>\n" );
document.write( "we use the formula<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%281%2F8%29%2A4+%2B+%281%2F12%29%2A4+%2B+%281%2F12%29%2Ax+=+1 ALIGN=MIDDLE  ALT=\"%281%2F8%29%2A4+%2B+%281%2F12%29%2A4+%2B+%281%2F12%29%2Ax+=+1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "we get<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4%2F8+%2B+4%2F12+%2B+x%2F12+=+1 ALIGN=MIDDLE  ALT=\"4%2F8+%2B+4%2F12+%2B+x%2F12+=+1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "adding the fractions, we get<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+5%2F6+%2B+x%2F12+=+1 ALIGN=MIDDLE  ALT=\"+5%2F6+%2B+x%2F12+=+1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "subtract 5/6 to get<BR>\n" );
document.write( " <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%2F12+=+1%2F6 ALIGN=MIDDLE  ALT=\"x%2F12+=+1%2F6\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "multiply by 12 to get<BR>\n" );
document.write( " <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+2 ALIGN=MIDDLE  ALT=\"x+=+2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "So, the 3 hp pump must work and additional 2 hours. </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );