Solving problem N3739 Bayesian probability theory

Solving problem N3739 Bayesian probability theory

3739. From the first machine they get 80% for the assembly, and from the second - 20% of the same parts. On the first machine, the defect is 1%, and on the second - 4%. Proven detail was defective. Determine the probability that this part is made: 1) on the first machine; 2) on the second machine

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