document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=693604>Question 693604</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I am really horrible at word problems, and I don't really understand logarithms that well. So here it goes.\r<BR>\n" );
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document.write( "The intensity of an earthquake, measured on the Richter scale, is given by the log (I/I subscript 0), where I subscript 0 is the intensity of an earthquake of certain small size\r<BR>\n" );
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document.write( "In 2008 the earthquake in Rhodes, Greece measured 6.7 on the Richter Scale.<BR>\n" );
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document.write( "A) express this intensity I in terms of I (subscript 0)\r<BR>\n" );
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document.write( "B) in 2008 the earthquake in Sichuan, China, measured 8.0 on the Richter scale. Express this intensity I in terms of I (subscript 0).\r<BR>\n" );
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document.write( "C) How many more times intense was the earthquake in china than the earthquake in Greece? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #427486 by </B><A HREF=/tutors/aboutme.mpl?userid=solver91311><B>solver91311(24713)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=solver91311><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=solver91311><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=427486\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <font face=\"Times New Roman\" size=\"+2\">\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE \ \ \ \ \ \ \ \ \ \ \log\left(\frac{I_G}{I_0}\right)\ =\ 6.7\">\r<BR>\n" );
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document.write( "Since the definition of logarithms says:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE \ \ \ \ \ \ \ \ \ \ y = \log_b(x) \ \ \Rightarrow\ \ b^y = x\">\r<BR>\n" );
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document.write( "and we are assuming the base of the given log to be 10 because it is not specified, we can write:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE \ \ \ \ \ \ \ \ \ \left(\frac{I_G}{I_0}\right)\ =\ 10^{6.7}\">\r<BR>\n" );
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document.write( "And then\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE \ \ \ \ \ \ \ \ \ I_G\ =\ I_0\,\cdot\,10^{6.7}\">\r<BR>\n" );
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document.write( "Similarly\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE \ \ \ \ \ \ \ \ \ I_C\ =\ I_0\,\cdot\,10^{8}\">\r<BR>\n" );
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document.write( "and finally:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE \ \ \ \ \ \ \ \ \ \frac{I_C}{I_G}\ =\ \frac{I_0\,\cdot\,10^{8}}{I_0\,\cdot\,10^{6.7}}\ =\ 10^{8\,-\,6.7}\ =\ 10^{1.3}\ \approx\ 20\">\r<BR>\n" );
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document.write( "You can usually do relative size of earthquakes in your head.  A whole number is 10 times the intensity of the next lower whole number.  So two whole numbers is 100 times, etc.  0.1 is a 1.25 multiplier, 0.2 is approximately a 1.6 multiplier, and 0.3 is very close to a 2 multiplier.  So your 1.3 difference is worth 10 (for the whole number) times 2 (for the 0.3) for a total of 20.\r<BR>\n" );
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document.write( "John<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE e^{i\pi}\ +\ 1\ =\ 0\"><BR>\n" );
document.write( "<font face=\"Math1\" size=\"+2\">Egw to Beta kai to Sigma</font><BR>\n" );
document.write( "My calculator said it, I believe it, that settles it<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE \ \ \ \ \ \ \ \ \ \ \"> </SPAN>\n" );
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