To calculate the expected value of a random variable, multiply each possible outcome by its corresponding probability and then sum all these values. For a discrete random variable, the formula is:
E(X) = Σ [x * P(x)]
Where:
- x represents each possible outcome,
- P(x) is the probability of each outcome,
- Σ denotes the sum over all possible outcomes.
The expected value gives you the average outcome if the experiment were repeated many times. In the context of games like lotteries, it helps estimate the long-term average gain or loss based on probabilities and payouts.
E(X) = Σ [x * P(x)]
Where:
- x represents each possible outcome,
- P(x) is the probability of each outcome,
- Σ denotes the sum over all possible outcomes.
The expected value gives you the average outcome if the experiment were repeated many times. In the context of games like lotteries, it helps estimate the long-term average gain or loss based on probabilities and payouts.