The answer to this question is B
Answer: a) 
Step-by-step explanation:
Given : 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 detects theft with a probability of .99 independently of the others .
Probability for independent events
occurs together =
.
Then, the probability that when a theft occurs, all four systems will detect it
= (0.99) x (0.99) x (0.99) x (0.99)

Hence, the probability that when a theft occurs, all four systems will detect it is
.
Hence, the correct answer is a)
.
Answer:
-7/13
Step-by-step explanation:
If you need to you can write it out. the answer is X=14
15.12m2 just finished the test