On average, a major earthquake (Richter scale 6.0 or above) occurs three times a decade in a certain California county. Find the probability that at least one major earthquake will occur within the next decade.
A).7408
B).1992
C).1494
D).9502

Question

Quizplus · Accepted Answer

The probability of at least one major earthquake occurring is 1 minus the probability of no earthquakes occurring. The average rate is 3 per decade, so using the Poisson distribution: P(X=0) = e^(-3) * 3^0 / 0! = e^(-3). Therefore, the probability of at least one is 1 - e^(-3) ≈ 0.9502.

On Average, a Major Earthquake (Richter Scale 6