Solution to: The Prince and the Pearls

The probability that the chosen vase does not contain a white pearl is (10-5)/10 = 1/2. The probability that the chosen vase does not contain a black pearl is (10-4)/10 = 3/5. The probability that the chosen vase does not contain any pearl is therefore 1/2 × 3/5 = 3/10 (which is 30%).

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