Question 1120980
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<pre>
Usually (at the school math level) you are given a large finite set of events  A  and its subset of events  B.



The events of  A  are (<U>usually</U>) supposed to be equally likely, and a typical question is 

    "what is the probability for the event from A to be the event from B ?"



In this situation, the probability is simply the ratio of numbers  |B|  to  |A|


    P(B) = {{{abs(B)/abs(A)}}},


where |A| is the number of elements/events in the set A,  while  |B|  is the number of elements/events in the subset B.
</pre>

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