document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=977920>Question 977920</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hi tutors, can u help me answer this? Thanks\r<BR>\n" );
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document.write( "A ball starts rolling from the centre of a 3 m x 4 m room in a direction of 45&#730; to the walls. It rolls in a straight line except when it bounces off a wall and it does that at an angle of 45&#730;.\r<BR>\n" );
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document.write( "After it has travelled 20 m, how many times has it bounced off a wall?\r<BR>\n" );
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document.write( "A. 5<BR>\n" );
document.write( "B. 6<BR>\n" );
document.write( "C. 7<BR>\n" );
document.write( "D. 8<BR>\n" );
document.write( "E. 9 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #599424 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=599424\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A ball starts rolling from the centre of a 3 m x 4 m room in a direction of 45 degs to the walls. It rolls in a straight line except when it bounces off a wall and it does that at an angle of 45 degs.\r<BR>\n" );
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document.write( "After it has travelled 20 m, how many times has it bounced off a wall?<BR>\n" );
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document.write( "It will bounce off the wall that's 4 m long first then the 3 m wall.\r<BR>\n" );
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document.write( "Draw it as 2 parallel walls 4 m apart.<BR>\n" );
document.write( "Each pair of bounces it travels 4*sqrt(2) meters.<BR>\n" );
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document.write( "20/(4sqrt(2)) =~ 3.55 pairs of bounces<BR>\n" );
document.write( "--> 7 bounces\r<BR>\n" );
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document.write( "A. 5<BR>\n" );
document.write( "B. 6<BR>\n" );
document.write( "C. 7<BR>\n" );
document.write( "D. 8<BR>\n" );
document.write( "E. 9 </SPAN>\n" );
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