Question

the seismic activity density of a region is the ratio of the number of earthquakes during a given time span to the land area affected. a state had 424 earthquakes over a given time span and a land area of 71,300 square miles. what is the seismic activity density for this state? round to the nearest ten thousandth, if necessary. 0.0046 earthquakes per square mile 0.0059 earthquakes per square mile 168.1604 earthquakes per square mile 179.0049 earthquakes per square mile

Explanation:

Step1: Recall the formula for seismic activity density

Seismic activity density = $\frac{\text{Number of earthquakes}}{\text{Land - area affected}}$

Step2: Substitute the given values

Number of earthquakes = 424, Land - area affected = 71300 square miles. So, Seismic activity density=$\frac{424}{71300}$

Step3: Calculate the value

$\frac{424}{71300}\approx0.0059467$

Step4: Round to the nearest ten - thousandth

Rounding 0.0059467 to the nearest ten - thousandth gives 0.0059

Answer:

B. 0.0059 earthquakes per square mile