Probability Distribution Problem

[joypav]

Suppose that cars pass a certain intersection at a rate of 30 miles per hour. What is the probability that during a three-minute interval, no cars will pass the intersection?

I am really just wondering which distribution to use. I thought is should be Poisson because it is asking for events occurring during a certain time period. But it doesn't say how many cars pass the intersection on average?

 

[Opalg]

Suppose that cars pass a certain intersection at a rate of 30 miles per hour. What is the probability that during a three-minute interval, no cars will pass the intersection?

I am really just wondering which distribution to use. I thought is should be Poisson because it is asking for events occurring during a certain time period. But it doesn't say how many cars pass the intersection on average?

I think you mean 30 cars per hour, not 30 miles per hour. The speed at which the cars pass does not seem to be relevant.

If it's 30 cars per hour, then on average a car passes every 2 minutes. You should be able to use this to construct a Poisson distribution to model the flow of traffic.

 

[joypav]

My review definitely says miles per hour. I was thinking it may be a typo too, but wanted to make sure I wasn't just misunderstanding. Thank you