Explain
Because all outcomes are equally weighted, the probability you are looking for is given by
Number of favorable eventsTotal number of events Number of favorable events
Total number of events
In your case: 6 or Even outcome={2,4,6}
6
or Even outcome= {2,4,6}
and Outcomes={1,2,3,4,5,6}
Outcomes
{1,2,3,4,5,6}
Number of favourable eventsTotal number of events
3/6 = 1/2