SOLUTION: For safety reasons, four different alarm systems were installed in the vault containing the safety deposit boxes at a Beverly Hills bank. Each of the four systems will fail to dete

Algebra ->  Probability-and-statistics -> SOLUTION: For safety reasons, four different alarm systems were installed in the vault containing the safety deposit boxes at a Beverly Hills bank. Each of the four systems will fail to dete      Log On


   



Question 1084395: For safety reasons, four different alarm systems were installed in the vault containing the safety deposit boxes at a Beverly Hills bank. Each of the four systems will fail to detect theft with a probability of .01 independently of the others. What is the probability that when a theft occurs, none of four systems will detect it?
   (.99)^4
   (.01)^4
   (.01) * 4
   4 * (.01) * (.99)^3
   4 * (.99) * (.01)^3

Answer by jorel1380(3719) About Me  (Show Source):
You can put this solution on YOUR website!
The probability of failure is .01, so the probability that all four will fail at the same time is .01x.01x.01x.01, or (.01)^4, which equals 0.00000001. ☺☺☺☺