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what is mathematical expectation of a random variable
In probability theory, the expected value of a random variable is a key aspect of its probability distribution.
what is mathematical expectation of a discrete random variable
The expected value of a discrete random variable is the probability-weighted average of all its possible values.
can you explain about The expected value of a discrete random variable is the probability-weighted average of all its possible values.
In other words, each possible value the random variable can assume is multiplied by its probability of occurring, and the resulting products are summed to produce the expected value.
does expected value apply to an absolutely continuous random variable
Expected value also applies to an absolutely continuous random variable, except that an integral of the variable with respect to its probability density replaces the sum.

Question: what is a real world application
Self-contained rewrite: what is a real world application of expected value