Answer:
P(rolling a 2) = 1/6
P(not rolling a 2) = 5/6
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Reason:
A number cube has 1 side that shows "2" out of 6 sides total. The probability of rolling a "2" is 1/6
The other 5 sides don't have "2" on them, so that's why 5/6 is the probability of not rolling a "2"
The two fractions (1/6 and 5/6) add up to 6/6 = 1 to represent 100% of the possibilities. Either you roll a 2 or you don't.