15 a congested computer network has a 1 chance of losing a

15. a congested computer network has a 1 % chance of losing a data packet and packet loses are independent events. An email message requires 100 packets. 16. Compute the values of (a) P(20,5) , (b) 0! (c) c(20,3) (d) 7!

Solution

Here p = 1% = 0.01 and n =100

As p is very small and np is finite we can approximate to Poisson distribution with mean = np = 1

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b) P(X>=1) = 0.6321

c) P(X>=2) = 0.2642

d) Mean = 1 and std dev = 1

e) Here the events are independent and follow a binomial with p = prob (X>=2) = 0.2642

n = 10

Hence P(y>=1) =0.9535

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16) P(20,5) = 1860480

b) 0! =1

c) (20,3) = 6840

d) 7! = 5040