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 							  measure L(A) and has nothing to do with its position and
 							  shape.
 						- The **Frequency** Interpretation of Probability
-							-
+							- Let E be an random experiment, A be an random event.
+							  Suppose that E was repeated n times under similar conditions.
+							  Let fn (A) be the times that A occurs. The ration
+							  $$Fn (A) =
+							  fn (A) /
+							  n$$
+							  is said to be the frequency of event A in the n trials. If n is
+							  large enough, the probability of event A will be approximated
+							  by Fn (A).
 					- Problems of Each Interpretation of Probability
 					- Similarity of the Above Interpretations of probability
 					- Summary