document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=638291>Question 638291</A>: <I><SPAN STYLE=\"word-break: break-all;\"> In my question there is a diagram which shows a circle with a circumference of 1cm being rolled around an equilateral triangle with sides of length 1cm.\r<BR>\n" );
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document.write( "The circle is positioned haalfway between the top and bottom of one side of the triangle\r<BR>\n" );
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document.write( "How many COMPLETE TURNS does the circle make as it rolls around the triangle ( without slipping) to its original starting position.  I know that the answer is 4, please could someone explain in simple terms why it is 4.\r<BR>\n" );
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document.write( "Thankyou </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #402111 by </B><A HREF=/tutors/aboutme.mpl?userid=MathLover1><B>MathLover1(20850)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=MathLover1><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=MathLover1><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=402111\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> an equilateral triangle with sides of length 1cm has a perimeter of <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3+cm ALIGN=MIDDLE  ALT=\"3+cm\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "if the circle rolls along a straight line of length <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3+cm ALIGN=MIDDLE  ALT=\"3+cm\"   DISABLED_style= \"max-width:90%; height:auto;\" > (without slipping), it would need to make <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=three ALIGN=MIDDLE  ALT=\"three\"   DISABLED_style= \"max-width:90%; height:auto;\" > complete turns \r<BR>\n" );
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document.write( "the perimeter of the triangle <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=also ALIGN=MIDDLE  ALT=\"also\"   DISABLED_style= \"max-width:90%; height:auto;\" > makes another turn (sum of external angles = 360), so the <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=circle ALIGN=MIDDLE  ALT=\"circle\"   DISABLED_style= \"max-width:90%; height:auto;\" > will need to make <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4 ALIGN=MIDDLE  ALT=\"4\"   DISABLED_style= \"max-width:90%; height:auto;\" > turns in all\r<BR>\n" );
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