document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=134441>Question 134441</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I tried on this problem already (not from a textbook) and I'm not sure if I'm getting it, I've got answers ranging from 18 mins to 8.89 minutes.  Here's the problem:\r<BR>\n" );
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document.write( "Jack can wash a car in 16 minutes; Jill can wash the same car in 20 minutes.  How long will it take both of them working together to wash the car?\r<BR>\n" );
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document.write( "This is what I've done:  (16 + 20) / 2 = 18 mins\r<BR>\n" );
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document.write( "I've also tried using the example of the solution to problem 133568 and I got 8.89 mins.\r<BR>\n" );
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document.write( "I'm not sure which is correct and I'd really appreciate the help.  Thank you. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #98337 by </B><A HREF=/tutors/aboutme.mpl?userid=checkley71><B>checkley71(8403)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=checkley71><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=98337\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> YOU ARE USING THE WRONG EQUATION FOR THIS PROBLEM.<BR>\n" );
document.write( "THE PROPER EQUATION IS THE PRODUCT DIVIDED BY THE SUM OF THE 2 TIMES.<BR>\n" );
document.write( "16*20/(16+20)=320/36=8.889 MINUTES TO WASH THE CAR WORKING TOGETHER.  </SPAN>\n" );
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