Combinatorics 2 variables A very simple question to answere for anyone with basic knowledge of statistics I would presume: For a (large) fleet of two different vehicle types A and B, with equal fleet share (50%), what are the chances of type A being involved in an accident between 2 vehicles. I.e if I pick 100 random accidents involving 2 vehicles how many would statistically be between A and B, A and A, and B and B?

We have $P(A $involved$) = 0.5 , P(B$ involved$) = 0.5$ Using the AND rule, we find the probability of A and B occuring by multiplying the probabillties. Therefore, the probability of:

$$P(A \text{and} B) = 0.5 *0.5=0.25$$ $$P(B \text{and} B) = 0.5 *0.5=0.25$$ $$P(B \text{and} A) = 0.5 *0.5=0.25$$ $$P(A \text{and} A) = 0.5 *0.5=0.25$$