Question

over a 200 - year period, a volcano erupted once. according to this information, what is the yearly frequency of volcanic eruption?
a. 1%
b. 20%
c. 0.5%
d. 99%

Explanation:

Step1: Calculate the frequency

The formula for frequency is \( \text{Frequency}=\frac{\text{Number of events}}{\text{Total time}} \). Here, the number of volcanic eruptions is \( 1 \), and the total time is \( 200 \) years. So the frequency is \( \frac{1}{200} \).

Step2: Convert to percentage

To convert a fraction to a percentage, we use the formula \( \text{Percentage}=\frac{\text{Numerator}}{\text{Denominator}}\times100\% \). Substituting \( \frac{1}{200} \) into the formula: \( \frac{1}{200}\times100\% = 0.5\% \).

Answer:

C. 0.5%