As per the question seems, the expected value can be positive, negative or zero.
The given question is of probability, which cannot be negative so don't get confused between expected values and probability, expected value and be negative, positive or zero.
What is probability?
Probability can be defined as the ration of favorable outcomes to the total number of events.
If person playing different games in casino , the probability of that person winning could be varying from 0/7 to 7/7 which implies that person can win from zero games to all games. If that person wins all the 7 games that mean he the gain in values, but if the loses 1 games or more games there than he supposed have gain or have loosen expected values so it can be positive, negative or zero. however the person loosen every game their is certain negative expected values.
Thus, The expected value can be positive, negative or zero.
Learn more about probability here:
https://brainly.com/question/14290572
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