Question 84
MediumOriginal questionAt a school, 35% of the students live in the hostel and 65% are day scholars. 40% of hostel students and 20% of day scholars score an A. What is the probability that a student picked at random scores an A?
Show the answer and explanation
CorrectNot quiteAnswer A
Correct answer: A
Explanation
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Worth noting
0.3 averages 40% and 20% as if the two groups were the same size.
- Concept
- The theorem of total probability
- Typical timeTypical
- 90 s
- Your timeYours
- —
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Ten questions from Conditional Probability & Bayes' Theorem, at your own pace.