document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=672824>Question 672824</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A and B do a work together in five days If A do the work with double speed and B with half the speed then they do the work in 4 days together find A alone do the work in how much time. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #418335 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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/cgi-bin/show-face.mpl?user=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=418335\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A and B do a work together in five days<BR>\n" );
document.write( " If A do the work with double speed and<BR>\n" );
document.write( " B with half the speed then they do the work in 4 days together<BR>\n" );
document.write( " find A alone do the work in how much time.<BR>\n" );
document.write( ":<BR>\n" );
document.write( "let a = A's time alone<BR>\n" );
document.write( "let b = B's time alone<BR>\n" );
document.write( "then<BR>\n" );
document.write( ".5a = A's time when working twice as fast<BR>\n" );
document.write( "and<BR>\n" );
document.write( "2b = B's time when working half as fast<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Let the completed job = 1<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Write a shared work equation for each scenario<BR>\n" );
document.write( ":<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=5%2Fa ALIGN=MIDDLE  ALT=\"5%2Fa\"   DISABLED_style= \"max-width:90%; height:auto;\" > + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=5%2Fb ALIGN=MIDDLE  ALT=\"5%2Fb\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 1<BR>\n" );
document.write( "get rid of the denominators, mult by ab<BR>\n" );
document.write( "5b + 5a = ab<BR>\n" );
document.write( "and<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4%2F%28.5a%29 ALIGN=MIDDLE  ALT=\"4%2F%28.5a%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4%2F%282b%29 ALIGN=MIDDLE  ALT=\"4%2F%282b%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 1<BR>\n" );
document.write( "multiply by 2ab to get rid of the denominators<BR>\n" );
document.write( "4b(4) + 4a = 2ab<BR>\n" );
document.write( "16b + 4a = 2ab<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Use elimination here, mult the 1st equation by 4, mult the 2nd eq by 5<BR>\n" );
document.write( "then subtract the 1st from the 2nd<BR>\n" );
document.write( "80b + 20a = 10ab<BR>\n" );
document.write( "20b + 20a = 4ab<BR>\n" );
document.write( "------------------subtraction eliminates a<BR>\n" );
document.write( "60b + 0 = 6ab<BR>\n" );
document.write( "divide both sides by b<BR>\n" );
document.write( "60 = 6a<BR>\n" );
document.write( "a = 60/6<BR>\n" );
document.write( "a = 10 days working alone </SPAN>\n" );
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