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Lesson 2 · Conditional Probability, Bayes and Independence · Probability Theory
Step 1 of 7Pretest
Have a go before we teach it — wrong is fine, and it helps.
Urn 1 contains 3 white and 2 black balls; urn 2 contains 1 white and 4 black balls. An urn is chosen by a fair coin toss and one ball is drawn from it at random. The drawn ball is white. What is the probability that it came from urn 1?