Solution:

Let represent the driver being a scooter driver, represent the driver being a car driver, and represent the driver being a truck driver. Assume that the person is involved in an accident.

total number of drivers

Then

Because a headed coin has a head on both sides, it will display one.

Also accident of a scooter driver

And accident of a car driver

And accident of a truck driver

Because a headed coin has a head on both sides, it will display one. Given that the driver was involved in an accident, the probability that he was a scooter driver is .

We have used Bayes’ theorem to arrive at our conclusion.

We may now retrieve the result by swapping the values.