Question 121
HardOriginal questionA shop gets 70% of its eggs from farm P and 30% from farm Q. Of P's eggs, 5% are cracked; of Q's, 10% are cracked. An egg is picked at random.
The egg is not cracked. What is the probability that it came from farm P?
Show the answer and explanation
CorrectNot quiteAnswer C
Correct answer: C
Explanation
, and .
.
Worth noting
0.95 is , the reverse conditional; the answer is only a little above P's share of 0.7.
- Concept
- Bayes' theorem
- Typical timeTypical
- 150 s
- Your timeYours
- —
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