An event may contain sample points that are not in the original sample space of the experiment.
For example, the experiment of rolling two dice has the following sample space: $$\{ ( 1,1 ) , ( 1,2 ) , ( 1,3 ) , ( 1,4 ) , ( 1,5 ) , ( 1,6 ) , ( 2,1 ) , ( 2,2 ) , ( 2,3 ) , ( 2,4 ) , ( 2,5 ) , ( 2,6 ) \text {, }$$
$( 3,1 ) , ( 3,2 ) , ( 3,3 ) , ( 3,4 ) , ( 3,5 ) , ( 3,6 ) , ( 4,1 ) , ( 4,2 ) , ( 4,3 ) , ( 4,4 ) , ( 4,5 ) , ( 4,6 )$, $( 5,1 ) , ( 5,2 ) , ( 5,3 ) , ( 5,4 ) , ( 5,5 ) , ( 5,6 ) , ( 6,1 ) , ( 6,2 ) , ( 6,3 ) , ( 6,4 ) , ( 6,5 ) , ( 6,6 ) \}$ However, the event of rolling a sum of at least 11 on the two dice is {11, 12}.

Question

Quizplus · Accepted Answer

An event must consist of outcomes that are within the original sample space of the experiment. The event of rolling a sum of at least 11 should be represented by pairs of dice outcomes that sum to 11 or more, such as $(5,6), (6,5), (6,6)$, not by the sums themselves.

An Event May Contain Sample Points That Are Not in the Original