Independent solution

How to solve this Independence question

Setup

Setup

Convert the no-accident probabilities into accident probabilities for the two employee classes.

pH=0.40,pL=0.10p_H=0.40,\qquad p_L=0.10

Model

Model

Calculate the probability that no employee has an accident.

P0=(0.60)2(0.90)2=0.2916P_0=(0.60)^2(0.90)^2=0.2916

Compute

Compute

Separate the exactly-one case according to whether the accident belongs to a high-risk or low-risk employee.

P1,H=2(0.40)(0.60)(0.90)2=0.3888P_{1,H}=2(0.40)(0.60)(0.90)^2=0.3888
P1,L=2(0.10)(0.90)(0.60)2=0.0648P_{1,L}=2(0.10)(0.90)(0.60)^2=0.0648
Pr(N1)=0.2916+0.3888+0.0648=0.7452\Pr(N\le1)=0.2916+0.3888+0.0648=0.7452

Answer

Answer

At most one employee has an accident with probability 0.7452.

0.7452(E)\boxed{0.7452\quad\text{(E)}}