Exercises 2

Successful evacuation depends on the available evacuation time. Analysis of typical fire development shows that:

A₁= short evacuation time → Pr(A₁) = 1%

A₂= medium evacuation time → Pr(A₂) = 20%

A₃= long evacuation time → Pr(A₃) = 79%

The probability of successful evacuation (B) is given by:

Pr(B| A₁) = 50%

Pr(B| A₂) = 75%

Pr(B| A₃) = 95%

Find Pr(B) by the law of total probability, i.e., the probability of sucessfull evacuation. Hint: Use MS Excel