Solution of problem N3960 probability theory

Solution of problem N3960 probability theory

3960. Electric bulbs are manufactured at two plants. The first plant produces 45% of the total number of light bulbs, the second - 55%. The production of the first plant contains 90% of standard lamps, the second - 80%. The store receives products from all two plants. What is the probability that the lamp purchased in the store will be standard?

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