An insurance company insured 2000 scooters and 3000 motorcycles. The probability of an accident involving a scooter is 0.01 and that of a motorcycle is 0.02. An insured vehicle met with an accident. Find the probability that the accidented vehicle was a motorcycle.
Given:
Company insured 2000 scooters and 3000 motorcycles
Let us assume U1, U2 and A be the events as follows:
U1 = choosing Scooter
U2 = choosing Motorcycle
A = accident involving vehicle
From the problem
⇒
⇒
⇒ P(A|U1) = P(accident involving scooter)
⇒
⇒ P(A|U2) = P(accident involving motorcycles)
⇒
Now we find
P(U2|A) = P(The vehicle involved in an accident is motorcycle)
Using Baye’s theorem:
⇒
⇒
⇒
⇒
⇒
∴ The required probability is .