Air bag manufactured by Aces(A)=57%
So, Probability
Air bag manufactured by Best (B) =26%
So, Probability
Airbag manufactured by Cool(C)=17%
So, Probability
Airbags made by Aces, Best, and Cool do not kill people at rates of 99%, 96%, and 87%, respectively.
Let K be the event which kill people.
Probability of Air bag made by A which kill people
Probability of Air bag made by B which kill people
Probability of Air bag made by C which kill people
If an airbag kills a passenger, calculate the probability that the airbag was manufactured by Cool
Using Baye's theorem:

Substitute the values of probabilities into formula
We get,

Now we calculate it and get probability
So,

So, 57.85% of passenger kills if the airbag was manufactured by Cool.