Got Homework?
Connect with other students for help. It's a free community.
Here's the question you clicked on:
 0 viewing
There are 25 students at a bus stop. It is known that on average, 3 buses arrive at the bus stop in every 20 minutes.
What is the probability that the waiting time for the next bus is at least 30 minutes?
State the assumptions you need to compute the above probabilities.
 one year ago
 one year ago
There are 25 students at a bus stop. It is known that on average, 3 buses arrive at the bus stop in every 20 minutes. What is the probability that the waiting time for the next bus is at least 30 minutes? State the assumptions you need to compute the above probabilities.
 one year ago
 one year ago

This Question is Closed

xEnOnnBest ResponseYou've already chosen the best response.0
I believe it has got to do with Poisson distribution but I am not sure how to start from it. :(
 one year ago

xEnOnnBest ResponseYou've already chosen the best response.0
So the number of buses has become the interval instead? But isn't time the only unit for the interval in poisson?
 one year ago

xEnOnnBest ResponseYou've already chosen the best response.0
Also, the question asked for the assumptions that were made in computing the probabilities. What assumptions have we made in this calculation? I don't understand what kind of assumptions have we made.
 one year ago

TributizedBest ResponseYou've already chosen the best response.0
nice prof pic lol..
 one year ago

xEnOnnBest ResponseYou've already chosen the best response.0
Also, to have X~Pois(20/3), and find P(X>=30)=1P(X<30), The P(X<30) is very close to 1. This would make P(X>=30)=11=0, which looks weird.
 one year ago

ZarkonBest ResponseYou've already chosen the best response.1
wouldn't it be Poisson\(\displaystyle\left(\frac{3}{20}\cdot 30\right)\)=Poisson(4.5)
 one year ago

xEnOnnBest ResponseYou've already chosen the best response.0
Why calculate the probability of X=0?
 one year ago

ZarkonBest ResponseYou've already chosen the best response.1
0 buses arriving in the first 30 mins
 one year ago

xEnOnnBest ResponseYou've already chosen the best response.0
OHH!!! wow!! This is smart!
 one year ago

ZarkonBest ResponseYou've already chosen the best response.1
time to teach..be back later
 one year ago

xEnOnnBest ResponseYou've already chosen the best response.0
wow! this feels counter intuitive but somewhat logical. i wouldn't have thought of it. It's like so there is zero buses during the first 30mins and so this probability is as good as there is at least a bus after this first 30mins. thanks!!
 one year ago

xEnOnnBest ResponseYou've already chosen the best response.0
ok sure! Thanks for you help!!!
 one year ago
See more questions >>>
Your question is ready. Sign up for free to start getting answers.
spraguer
(Moderator)
5
→ View Detailed Profile
is replying to Can someone tell me what button the professor is hitting...
23
 Teamwork 19 Teammate
 Problem Solving 19 Hero
 Engagement 19 Mad Hatter
 You have blocked this person.
 ✔ You're a fan Checking fan status...
Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.