Question

Probability of a 10 year flood to occur atleast once in the next 4 years is

• A. 25%
• B. 35%
• C. 50%
• D. 65%

Answer 1

The correct option is B 35%

Probability corresponding to 10 year return period is
$P=\frac{1}{10}=0.1$
The probabilty of flood occurring at least once in 4 years is
$=1-(1-P{)}^4=1-{0.9}^4=0.3439\approx 35\%$