Имеются 3 одинаковые урны. В первой находятся 4 белых и 6 черных шаров, во второй – 7 белых и 3 черных, в третьей – только черные. Наугад выбирается урна, наугад извлекается шар. Выбранный шар оказался черным. Какова вероятность того, что вынут шар из первой урны?

Имеются 3 одинаковые урны. В первой находятся 4 белых и 6 черных шаров, во второй – 7 белых и 3 черных, в третьей – только черные. Наугад выбирается урна, наугад извлекается шар. Выбранный шар оказался черным. Какова вероятность того, что вынут шар из первой урны?
- Предмет:
  Математика
- Автор:
  jamarion
- 6 лет назад

Ответы 1

по формуле полной вероятностиР=1/3*0,6+1/3*0,3+1/3*1=1/3*1,9=0,633по формуле БайесаР=1/3*0,6/0,633=0,316
- Автор:
  bessie
- 6 лет назад
- 0
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There are lots of ways to improve your fitness without having to join a gym. Joining a local sports team is a great way to spend your spare time and keep fit. You also get to meet lots of new people.
The benefits of getting fit
By keeping physically active, you're making sure that your joints and body organs are kept in good working order. Exercise can also help maintain your weight at a healthy level and can protect you against catching coughs and colds on a regular basis.
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• cycling or walking to school, college or work instead of driving or taking the bus
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