Equally Likely Outcomes
CONCEPTUALUnderstand that 'equally likely' means every outcome has exactly the same chance of occurring; identify whether a given situation has equally likely outcomes (a fair coin, a fair die, a spinner with equal sections) or unequally likely outcomes (a bag with more of one colour, a spinner with unequal sections)
Mastery Evidence
- Explain that a fair coin has equally likely outcomes because heads and tails each have the same chance
- Identify whether a spinner with unequal sections has equally likely outcomes or not, and explain why
- Give an example of a situation with equally likely outcomes and one without, explaining the difference
Assessment Prompt
“Can [child] tell the difference between a fair situation — like rolling a normal die where every number has the same chance — and an unfair one, like a bag with many more of one colour than another?”
Prerequisites1
- Ordering LikelihoodshardAges 9—10
Show full prerequisite tree
- Ordering Likelihoods hard
Understanding what 'equally likely' means is a specific case of comparing likelihoods that requires the general comparison skill first
- Likelihood Language hard
Comparing and ordering likelihoods requires first knowing the vocabulary of likelihood (certain, likely, unlikely, impossible)
Unlocks2
- Probability as a FractionhardAges 9—10
- Calculating Simple ProbabilityhardAges 10—11