7th Grade · Statistics & Probability
Impossible Event
7.SP.C.5
Definition
An event that cannot occur under any circumstances. Its probability is exactly 0 because there are 0 favorable outcomes.
Examples
- P(rolling a 7 on a standard die) = 0/6 = 0.
- P(drawing a purple card from a standard deck) = 0.
Key rule
Zero favorable outcomes in the sample space means the event is impossible.
Memory hook
P = 0 means it can never happen.