AI generatedProbabilityKS3 / GCSE

Recognising exhaustive outcomes

Recognising exhaustive outcomes.

  • Probability = favourable outcomes ÷ all outcomes when individual outcomes are equally likely.
  • A probability lies between 0 and 1; complementary probabilities sum to 1.
  • Experimental relative frequency estimates probability and can vary between samples.

Example 1

A counter is selected from numbers 1 to 5. Event A contains [1, 3, 5]; event B contains [2, 4]. Are A and exhaustive?

Yes: A ∪ B contains every possible number.

Exhaustive events cover the entire sample space. Check for missing outcomes. Mutually exclusive means no overlap, which is a separate property.

Example 2

A counter is selected from numbers 1 to 6. Event A contains [1, 3, 5]; event B contains [2, 4]. Are A and exhaustive?

No: [6] is missing.

Exhaustive events cover the entire sample space. Check for missing outcomes. Mutually exclusive means no overlap, which is a separate property.

Your turn

Question 1

A counter is selected from numbers 1 to 7. Event A contains [1, 3, 5, 7]; event B contains [2, 4, 6]. Are A and exhaustive?

Check answer
Yes: A ∪ B contains every possible number.

Exhaustive events cover the entire sample space. Check for missing outcomes. Mutually exclusive means no overlap, which is a separate property.

Question 2

A counter is selected from numbers 1 to 8. Event A contains [1, 3, 5, 7]; event B contains [2, 4, 6]. Are A and exhaustive?

Check answer
No: [8] is missing.

Exhaustive events cover the entire sample space. Check for missing outcomes. Mutually exclusive means no overlap, which is a separate property.

Question 3

A counter is selected from numbers 1 to 9. Event A contains [1, 3, 5, 7, 9]; event B contains [2, 4, 6, 8]. Are A and exhaustive?

Check answer
Yes: A ∪ B contains every possible number.

Exhaustive events cover the entire sample space. Check for missing outcomes. Mutually exclusive means no overlap, which is a separate property.

Question 4

A counter is selected from numbers 1 to 10. Event A contains [1, 3, 5, 7, 9]; event B contains [2, 4, 6, 8]. Are A and exhaustive?

Check answer
No: [10] is missing.

Exhaustive events cover the entire sample space. Check for missing outcomes. Mutually exclusive means no overlap, which is a separate property.

Question 5

A counter is selected from numbers 1 to 5. Event A contains [1, 3, 5]; event B contains [2, 4]. Are A and exhaustive?

Check answer
Yes: A ∪ B contains every possible number.

Exhaustive events cover the entire sample space. Check for missing outcomes. Mutually exclusive means no overlap, which is a separate property.