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Higher Education · Probability & Statistics

Random Variables

What is it

A random variable is a function that assigns a numerical value to each outcome of a random process — undergraduate study covers both discrete and continuous random variables, and their probability distributions rigorously.

Why it matters

Random variables are the formal mathematical language that lets probability theory be combined with algebra and calculus — without this formalism, it would be impossible to rigorously calculate expectations, variances, or the behaviour of complex random systems.

Exam tip

Always clarify whether a random variable is discrete or continuous before choosing a method — summing (for discrete) versus integrating (for continuous) are fundamentally different techniques, and applying the wrong one is a common early mistake.

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