Equally Likely Outcomes
Understand that equally likely means every outcome has exactly the same chance; identify equal and unequal chances in fair coins, fair dice, equal-section spinners, unequal-section spinners, and bags with different colour counts.
What a learner can do afterwards
- 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
1 · Read
Equally likely means each outcome has the same chance. A fair coin gives heads and tails the same chance. A fair die gives each of its 6 faces the same chance. A spinner with equal-size sections gives each section the same chance. If sections have different sizes, a larger section has a larger chance. If two sections share one colour, that colour has the combined chance of both sections. Landing on either of two colours has the combined chance of all their sections.
Mia has a bag with 4 red counters and 1 yellow counter. She pulls one out without looking. Red is more likely than yellow, because there are more red counters. Leo's bag has 5 green and 5 orange counters. The amounts match, so green and orange are equally likely. Same amount of each colour means equally likely. More of one colour means not equally likely.
To check if outcomes are equally likely, compare the amounts. The same amount for each outcome means equally likely. More of one than another means not equally likely.
Equally likely means every outcome has the exact same chance, so compare the amounts to check.
Linked YouTube videos: 'Basic Probability | Is It Equal, Likely, Unlikely, Certain, or Impossible?' by Turtlediary and 'Calculating Probability as a Fraction' by EasyTeaching; the videos belong to their channels, and only the link records were curated for os-taxonomy. The three readings and the nine extra practice questions were written for os-taxonomy. The six flashcards come from hoofer-content corpus fact candidates and are not individually source-tracked.
2 · Watch
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