Impossible event
An impossible event is an event that cannot happen in a given experiment.
Practice This ConceptMain explanation
Teacher explanation
If there are no favourable outcomes, the probability of the event is 0. Examples include getting 7 on a standard die or drawing a card of an impossible suit. The student should always check whether the event can actually occur before calculating anything else.
Example
Getting a 7 on one throw of a standard die is impossible, so its probability is 0.
Simple analogy
No favourable outcome means zero probability.
Common confusion
Students sometimes write a small fraction for an impossible event instead of 0.
Exam tip
If the event has no favourable outcomes, stop and write probability 0.
Answer writing and exam use
1-mark use
Write the exact meaning of impossible event in one clean line.
2-mark use
Define impossible event and add one example or condition.
3-mark use
Explain impossible event, show the method or example, and mention the common mistake.
Practice this concept with focused MCQs
Open the concept quiz intro first, review the test details, and then start a focused MCQ set from this concept only. Instant score and answer review are live now.
Help improve this page
Found something confusing, incorrect, or missing?