A governments department of transp reported that in 2009 air

A governments department of transp. reported that in 2009 airline A led all domestic in on-time arrivals for domestic fights with a rate of .84. Complete a-e

A. Using binomial distrib. what is the probability that in the next six flights, four flights will be on time?

B. Using binom. distrib. what is the probablitiy that in the next six flights, all six flights will be on time?

C. Using bion. distrib. what is the prob. that in the next six flights at least four flights will be on time?

D. What are the mean and std. deviation of the number of on-time flights n=6

E. What assumption do you need to make. Check all that apply

1. The prob. of observ. being classified as the event of interest pie is constant from observ. to observ.

2. The outcome of any observ. is depend. of the outcome of any other observ.

3. The outcome of any observ. is independ. of the outcome of any other observ.

4. Each observ. is classified into one of two mutually exclusive and collect. exhaustive categ.

Solution

n=6 , p=0.84

BINOMDIST function in excel is used to calculate the probabilities.

A) x=P(x=4)=0.19118

b) x=6

P(x=6)=0.3513

c) P(x>=4)=P(x=4)+P(x=5)+P(x=6)

P(x>=4)=0.9439

D) mean=np=6*0.84=5.04

sd=sqrt(npq)=0.8979

E) 1, 3 and 4 are correct.