7th Grade · Statistics & Probability

Non-Uniform Probability Model

7.SP.C.7

Definition

A probability model in which outcomes have different probabilities. Still valid as long as all probabilities are ≥ 0 and sum to 1.

Examples

  • A spinner where P(Red) ≠ P(Blue) ≠ P(Green) ≠ P(Yellow).
  • Real-world events are often non-uniform, unlike a fair die or coin.

Key rule

A model is valid whenever probabilities are non-negative and sum to exactly 1.

Memory hook

Not every outcome gets the same shot.