<PRE><B>Question 1138534</B>
magnitude R = log(intensity I).


8.6 = log(I) if and only if 10^8.6 = I.


7.7 = log(I) if and only if 10^7.7 = I.


divide 10^8.6 by 10^7.7 to get 10^(8.6 - 7.7) = 10^.9 = 7.943282347.


the earthquake with magnitude  of 8.6 on the richter scale is 7.943282347 times the intensity of the earthquake of 7.7 on the richter scale.





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