Solving problem N3825 Bayesian probability theory

Solving problem N3825 Bayesian probability theory

3825. Casting in blanks comes from two processing shops: 45% from the first shop, 55% from the second shop. Casting of the first workshop has 5% of marriage, the second 15% of marriage. Taken at random, the disc turned out to be without defect. What is the probability of its manufacture the first shop?

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Detailed solution. Decorated in Microsoft Word 2003 (Quest decided to use the formula editor)