Exam-style question
Try this first
For independent events A and B with P(A) = 0.5 and P(B) = 0.5, find P(A and B).
- A.0.25
- B.3.25
- C.-2.75
- D.0.5
Model answer
What a good answer should say
- The correct answer is 0.25.
This answer is tied to the objective: M1 Understand and use mutually exclusive and independent events when calculating probabilities; link to discrete and continuous distributions..
Explanation
Why this works
Use the explanation to connect the worked answer back to M1 Understand and use mutually exclusive and independent events when calculating probabilities; link to discrete and continuous distributions..
The distractors change the result or the form of the answer. The canonical solution reaches 0.25, so 0.25 is the only option consistent with the working.
Maths method check
- Topic focus: Statistics.
- Question style: practice.
- Reasoning demand: application.
- Check the operation, notation, units, and final answer form against the question before moving on.
Common mistake
No common mistake is linked to this question yet.