document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=352577>Question 352577</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Each of two brothers can wash a car in 1 hour; however their sister can wash the car in 45 minutes.If all three work together, how long will it take to wash the car? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #251977 by </B><A HREF=/tutors/aboutme.mpl?userid=nerdybill><B>nerdybill(7384)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=nerdybill><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=nerdybill><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=251977\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Each of two brothers can wash a car in 1 hour; however their sister can wash the car in 45 minutes.If all three work together, how long will it take to wash the car?<BR>\n" );
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document.write( "Rate of each brother: 1 car per 1 hour = 1/1<BR>\n" );
document.write( "Rate of sister: 1 car per 45 min = 1 car per .75 hour = 1/.75<BR>\n" );
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document.write( "Let x = time (hours) for all three working together<BR>\n" );
document.write( "then<BR>\n" );
document.write( "x(1/1 + 1/1 + 1/.75) = 1<BR>\n" );
document.write( "x(1 + 1 + 1/.75) = 1<BR>\n" );
document.write( "multiplying both sides by .75:<BR>\n" );
document.write( "x(.75 + .75 + 1) = .75<BR>\n" );
document.write( "x(2.5) = .75<BR>\n" );
document.write( "x = .75/2.5<BR>\n" );
document.write( "x = .3 hour<BR>\n" );
document.write( "or<BR>\n" );
document.write( "x = 18 minutes </SPAN>\n" );
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