Question

Flights arriving to DTW might be national or international. Assume that one out of every five national flights is followed by an international flight. If in the long run 25 percent of the flights are national, what fraction of international flights are directly followed by a national flight

Answer 1

Answer:

1/15

Step-by-step explanation:

Given

1 out of every 5 national flight is followed by an international flight.

p = 1/5

q = 1 - p

q = 1 - 1/5

q = 4/5

π0 = 0.25

We want to determine

p:the fraction of international flights that are followed by a national flight.

Let X = 0

If the nth flight is national

Let X = 1

if the flight is international

This gives rise to a two state Markov chain with transition probability as follows

P = (4/5. 1/5. p. 1-p)

The long run proportion are the below solution gotten from the Markov chain above

π0 = 4/5π0 + pπ1 ----- 1

π1 = 1/5π0 + (1 - p)π1---- 2

π0 + π1 = 1 -----------. 3

Solving the above equations,

We have

Substitute 0.25 for π0 in (3)

0.25 + π1 = 1

π1 = 1 - 0.25

π1 = 0.75

Solving 1 and 3

Substitute 0.75 for π1 and 0.25 for π0 in (1)

0.25 = 4/5 * 0.25 + 0.75p

0.25 = 0.2 + 0.75p

0.75p = 0.25 - 0.2

0.75p = 0.05

p = 0.05/0.75

P = 1/15 or 0.0667(6.67%)

So, one out of every 15 international flights is followed by a national flight (or 6.66 percent)