A lab network consisting of 18 computers was attacked by a c

A lab network consisting of 18 computers was attacked by a computer virus. This virus enters each computer with probability 0.25, independently of other computers. Use R commands to answers the following questions. Find the probability that the virus enters exactly 10 computers. Find the probability that the virus enters at least 5 computers. Find the probability that the virus enters at most 12 computers. Find the probability that the virus enters more than 8 computers. Find the probability that number of computers among the 18 that involve virus attack exceeds the expected number by more than one standard deviation.

Solution

Answer:

a) 18C10*(0.25)^10*(0.75)^8

b) 1- [18Cn(0.25)^n*(0.75)^(18-n)]

c) 1- [18C13(0.25)^14*(0.75)^(18-15)]

d) 18cn*(0.25)^n*(0.75)^(18-n) { n = 1 to 8 }