In a Poisson probability problem the rate of errors is one e

In a Poisson probability problem, the rate of errors is one every two hours. To find the probability of three defects in four hours, which lambda (mean) and x variable values should be used?

? = 2, x = 3

?= 3, x = 2

?= 6, x =2

? = 1, x = 2

?= 3, x =6

Solution

Answer: ? = 2, x = 3