Question

The probability of a 10 years flood to occur at least once in the next 5 years is

• A. 35%
• B. 41%
• C. 60%
• D. 65%

Answer 1

The correct option is B 41%

Favorable probability
$\left(p\right)=\frac{1}{10}=0.1$
Unfavorable probability (q)
$=1-p=1-0.1=0.9$
Probability to flood occur atleast once in the next 5 year
$=1-q^n$
$=1-(0.9{)}^5$
$=0.40951$
$\simeq 0.41or41\%$