An event has a theoretical probability of 20%. Which of the following must be true?

Question

Its experimental probability will always be 20%.

The experimental probability of its complement will always be 80%.

The theoretical probability of its complement will always be 80%.

The theoretical probability of its complement will always be -20%.

Answer 1

You can not say experimental probability will ALWAYS be the same. That is the thing about experiments.
The complement = 1 - p = 1 - .2 = .8
so I would pick
theoretical complement = 80%

Answer 2

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