Solution of problem N4249 probability theory

Solution of problem N4249 probability theory

4249. The device consists of two nodes, which during operation can independently fail from each other. Let the probability of failure-free operation of the first unit during the warranty period equal to 0.75, and the second - 0.8. Find the likelihood that during the warranty period the device: a) will work properly; b) will fail (i.e. at least one of the components of the device will fail).

Additional information:

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