Solving problem N3824 Bayesian probability theory

Solving problem N3824 Bayesian probability theory

3824. Casting in blanks comes from two preparation shops: from the first shop - 70%, from the second shop 30%. Casting of the first workshop has 10% of the marriage, casting from the second - 20% of the 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)