Question

5.22 Ship collisions in the Houston Ship Channel are rare. Suppose the number of collisions are Poisson distributed, with a mean of 1.2 collisions every four months.
a. What is the probability of having no collisions occur over a four-month period?
b. What is the probability of having exactly two collisions in a two-month period?
c. What is the probability of having one or fewer collisions in a six-month period? If this outcome occurred, what might you conclude about ship channel conditions during this period? What might you conclude about ship channel safety awareness during this period? What might you conclude about weather conditions during this period? What might you conclude about lambda?

5.26 A high percentage of people who fracture or dislocate a bone see a doctor for that condition. Suppose the percentage is 99%. Consider a sample in which 300 people are randomly selected who have fractured or dislocated a bone.

a. What is the probability that exactly five of them did not see a doctor?

b. What is the probability that fewer than four of them did not see a doctor?

c. What is the expected number of people who would not see a doctor?

Answer 1