Answer:
The answer is .31
Explanation:
The initial probability that tropical storm Isaac would become a hurricane was 0.69. We denote this event by A.
The probability that Isaac would not become a hurricane is the complement of event A, we denote the complement by Ac.
There are three probability axioms called Kolmogorov's axioms and from those axioms, we can deduce some useful rules for calculating probabilities.
This is one of them:
The probability of an event's complement (or the probability that the event will not happen) is 1 minus the probability that it will.
P(Ac)= 1- P(A)
P(Ac)= 1-0.69= 0.31