The table shows different flood types and their frequencies.
Total frequency of all flood types = 18 + 6 + 4 + 2 = 30
frequency of river flood = 6
Recall, probability is expressed as
number of favorable outcomes/number of total outcomes
Thus, the estimated probability that a flood in 2021 in that state will be a river flood is
6/30 = 0.2
By changing 0.2 to percentage, we have
0.2 x 100 = 20%
The correct option is C. 20%
