The cars passing a certain point as a function of time were counted during a traffic study of a city road. It was found that there was l0% probability of observing more than ten cars in an eight-minute interval.
a) Find the probability that exactly five cars will pass in a four-minute interval. What assumptions are being made?
b) Find the probability that fewer than two cars will pass in each of three consecutive intervals.
c) Find the probability that fewer than two cars will pass in exactly two of three consecutive intervals.
d) How long an interval should be used so that the probability of observing more than nine cars becomes 40%?