FORMULABANK

Sometimes the outcome space is uneven, meaning that the probabilities of different outcomes are not equal.

Example:

A spinner has three sections (Blue, Red, and Green). The sections are NOT of equal size, which means that the outcome space is uneven.

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What is the probability of the spinner landing on blue twice in a row?

Since the probability of landing on blue in each spin is $\frac{1}{2}$, the calculation is: $\frac{1}{2}·\frac{1}{2}=\frac{1}{4}$