The number of motor-vehicle fatalities in a city during a week is poissondistributed, with an average of 8 fatalities per week.

a) what is the probability that 12 fatalities occur in a specific week?
b) what is the probability that at least 12 fatalities occur in a specific week?
c) how many motor-vehicle fatalities would have to occur during a given week to conclude there are an unusually high number of events in that week?

a) 0.0481, b) 0.921, c) 13

Step-by-step explanation:

Since we have given that

We will use Poisson distribution:

a) What is the probability that 12 fatalities occur in a specific week?

b) What is the probability that at least 12 fatalities occur in a specific week?

c) How many motor-vehicle fatalities would have to occur during a given week to conclude there are an unusually high number of events in that week?

Hence, a) 0.0481, b) 0.921, c) 13