Suppose that, on average, the number of car accidents in Hong Kong are

lilyta79jd

lilyta79jd

Answered question

2021-11-27

Suppose that, on average, the number of car accidents in Hong Kong are 6 per day (which has 24 hours).
i. Determine the probability that at least χ accidents will occur in 12 hour period.
ii. In a two days, if there were 8 car accidents in Hong Kong, what is the probability that 2 accidents have occurred in the first 12 hours of the two days?

Answer & Explanation

breisgaoyz

breisgaoyz

Beginner2021-11-28Added 14 answers

Step 1 
There are two different types of probability distributions: discrete and continuous. Poisson distribution is a discrete probability distribution. 
Poisson distribution is deals with the probability of occurring a number of events in a period of time. There are only one parameter for Poisson distribution, that is λ. The mean and variance of the Poisson distribution is same as λ
Step 2 
Let X represent the total number of auto accidents in the 24-hour period in location H. It is assumed that six accidents occur every day. Therefore, X follows a Poisson distribution with parameter λ=6
XPoisson(6) 
i) If λ=6 for 24 hours, for 12 hours λ will be 62=3. Therefore, Y denotes a Poisson random variable with λ=3. The probability mass function of the Poisson distribution is given below. 
P(X=x)=eλ(λx)x! 
P(Yx) indicates the probability that at least x accidents occur in the 12 hour period and it be calculated and it can be calculated in the following way. 
P(Yx)=1P(X<x) 
=1i0x1e3(3i)i! 
So 1i=0x1e3(3l)i! is the required probability. 
Step 3 
ii) Let X indicates the number of car accidents in place H in 24 hours period. it is given that 6 accidents occurs in 24 hour period. Thus X follows a Poisson distribution with parameter λ=6. Thus for 48 hours the λ will be 12. 
P, the Poisson random variable for the number of accidents in the first 12 hours of a day, a week, or a month, shall be denoted. So λ=124=3. That is PPoisson(3). Q denotes the number of accidents in the rest 36 hours of 48 hour period. Thus λ=1234=9, thus QPoisson(9) 
Given that 8 car accidents are taken place and the probability for happening 2 accidents in the first 12 hour period has to be calculated (2 happened in the first 12 hours and 6 happened in the rest 36 hours). 
Therefore, 
P=P(P=2)P(Q=6)P(P+Q=8) 
=e3322!e9966!e121288! 
=0.224040.091090.06552 
0.31147 
Hence, 0.31147 is the required probability.

Do you have a similar question?

Recalculate according to your conditions!

New Questions in High school statistics

Ask your question.
Get an expert answer.

Let our experts help you. Answer in as fast as 15 minutes.

Didn't find what you were looking for?