## Random Variables

A random variable is a real valued function of the elements of sample space S which maps each possible outcome  to a real number specified by some rule. Random variables are denoted by capital Alphabet like X. If the random variable takes on finite or countably an infinite number of values then the random variable is a discrete random variable and if it takes uncountably infinite values then it is a continuous random variable. As we said earlier that the mapping is done by some rule; Probability mass function $$P_X(x)$$ defines that rule. $$P_X(x)$$ of a random variable is a function that...