document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=181315>Question 181315</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0974903620/algebrahomeworkh>Teaching Textbooks</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> Edwin can drop a piece of luggage off the top of headquarters and then record the results once every 4 minutes.  Hewitt can do the same every 5 minutes.  How many minutes will it take them together to drop their luggage and record the results a (combined) total of 18 times?\r<BR>\n" );
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document.write( "I tried this equation where x= minutes\r<BR>\n" );
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document.write( "5x + 4x = 18x\r<BR>\n" );
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document.write( "My problem is that the x's don't seem to have the same value.  I think I need to find out how many tries they each need and multiply that by the minutes, but I don't see how I can tell how many tries they each need!\r<BR>\n" );
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document.write( "Thanks for helping! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #135952 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=135952\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Edwin can drop a piece of luggage off the top of headquarters and then record the results once every 4 minutes. Hewitt can do the same every 5 minutes. How many minutes will it take them together to drop their luggage and record the results a (combined) total of 18 times? <BR>\n" );
document.write( "I tried this equation where x= minutes <BR>\n" );
document.write( "5x + 4x = 18x <BR>\n" );
document.write( "My problem is that the x's don't seem to have the same value. I think I need to find out how many tries they each need and multiply that by the minutes, but I don't see how I can tell how many tries they each need! <BR>\n" );
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document.write( "To do 18 drop tests, it would take Edwin 72 minutes, and Hewitt 90 minutes.<BR>\n" );
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document.write( "Then look at what part of the total test (18 drops) they do per minute.<BR>\n" );
document.write( "For Edwin, it's 1/72 (overall job per minute)<BR>\n" );
document.write( "For Hewitt, it's 1/90<BR>\n" );
document.write( "Now it's the same units, so you can add them.<BR>\n" );
document.write( "Together they do 1/72 + 1/90 = 5/360 + 4/360 = 9/360.<BR>\n" );
document.write( "That's the job/time, so invert that.<BR>\n" );
document.write( "360/9 = 40 minutes.<BR>\n" );
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document.write( "It's a tricky thing to visualize.<BR>\n" );
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