Lâplace's rule helps us to calculate the probability of an event, based on the sample space, since we have to perform a count. The rule says:[br][math]P\left(A\right)=\frac{Favour-Outomes}{Posible-Outcomes}[/math] That is to say, the probability of an event is the proportion between the number of favour outcomes of its occurrence, divided by the total number of outcomes of the experiment.[br]As long as we can describe and "count" the elements or outcomes of the sample space, we can easily apply this rule.

-Check the first example[br]- Check the sample space[br]-Check that the rule is verify with an example[br]- Repeat it for similar examples