Ontario · Grade 8
G8.D2
Grade 8 — Describe the likelihood that events will happen, and use that information to make predictions.
A note on this mapping: Ontario numbers its Data expectations per grade document and the specific numbering could not be verified line by line here, so this tag names the strand's OVERALL expectation rather than guessing at a specific one.
The 2 skills that cover it
- Complements, Or & AndCombine probabilities: the complement rule for "not", the addition rule for "or", and the multiplication rule for independent events.Read the lesson →
- Compound EventsWork out probabilities for experiments with more than one stage, and keep track of whether the first stage changes the second.Read the lesson →
What a student should be able to do
- Use P(not A) = 1 - P(A) to find the probability of a complement.
- Add probabilities for events that cannot both happen, and subtract the overlap when they can.
- Multiply probabilities for independent events joined by "and".
- Answer an "at least one" question by working with the complement instead.
- Find the probability of a two-stage event with replacement.
- Adjust both the numerator and the denominator when there is no replacement.
- Read a probability off an organised list or a two-way table of a sample space.
- Handle an "at least one" compound event through its complement.