AppliedMultiple choice
Which bag was it? · Part 2 of 3
Bag A holds 8 blue and 4 red balls; bag B holds 4 blue and 8 red. A fair coin picks one bag, and you draw from it without seeing which.
Start again. You draw three balls without replacement: two blue and one red. Now what is the probability of bag B?
- A0.30
- B1/3, by cancelling one blue against the red
- C0.50, since one red and one blue cancel exactly
- D0.70
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