Alarm systems

What is the probability that at least one alarm system will signal the theft of a motor vehicle when the efficiency of the first system is 90% and of the independent second system 80%?

Correct result:

p =  98 %

Solution:

p1=90/100=910=0.9 p2=80/100=45=0.8  p=100 (p1+p2p1 p2)=100 (0.9+0.80.9 0.8)=98%



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