document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=696696>Question 696696</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Two balls A and B rotate along a circular track. Ball A makes 4 full rotations in 120 seconds. Ball B makes 3 full rotation in 60 seconds. If they start rotating now from the same point, when will they be at the same starting point again? <BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #429332 by </B><A HREF=/tutors/aboutme.mpl?userid=god2012><B>god2012(113)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=god2012><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=god2012><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=429332\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Solution :\r<BR>\n" );
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document.write( "It is given that the speed of A is 4 rotations / 120 second <BR>\n" );
document.write( "This is equal to 1 rotation / 30 sec\r<BR>\n" );
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document.write( "Similarly , the speed of B is 3 rotations / 60 sec<BR>\n" );
document.write( "or 1 rotation / 20 second\r<BR>\n" );
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document.write( "Now, let us take the HCF of the time taken by both the balls A and B.<BR>\n" );
document.write( "i.e. HCF of 30 and 20 is 60.\r<BR>\n" );
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document.write( "Therefore , the balls meet at the starting point at every 60 mins interval. </SPAN>\n" );
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