Answer:
a) The mean number of cases is 0.14608 cases.
b) The probability that the number of cases is exactly 0 or 1 is 0.990.
c) The probability of more than one case is 0.010
d) No, because the probability of more than one case is very small
Step-by-step explanation:
We can model this problem with a Poisson distribution, with parameter:
a) The mean amount of cases is equal to the parameter λ=0.14608.
b) The probability of having 0 or 1 cases is:
c) The probability of more than one case is:
d) The cluster of 4 cases can not be due to pure chance, as it is a very high proportion of cases according to the average rate. Just having more than one case has a probability of 1%.