Question

Assume that the number of new visitors to a website in one hour is distributed as a Poisson variable with λ = 4.0. What is the probability in any given hour that two or more new visitors will arrive at the website?

Round to four decimals and use leading zeros if necessary.

Answer 1

Random variable X: Number of visitors to a website follows Poisson distribution with

If X follows Poisson with then

                               x = 0,1,2,...............

Where x! = 1 * 2 * 3.............*x

Here we have to find

                      

                                                    0! = 1

                      = 0.018316

                                              1! = 1

                      = 0.018316 * 4

                      = 0.073263

                      = 1 - [0.018316 + 0.073263]

                     = 1 - 0.091578

                     = 0.908422

                     = 0.9084             (Round to 4 decimal)

Probability in any given hour that two or more new visitors will arrive at the website is 0.9084