An electronic switching device occasionally malfunctions and may need to be replaced. The device is considered Satisfactory ifit makes on average no more than 0.2 errors per hour. A particular 5 hour period is chosen to test the device. If the occurrence of errors is a Poisson process.
I) What is the probability that a satisfactory device will be rejected?
II) What is the probability that a device will be considered satisfactory if the error rate = 0.25?