If it has been determined that the probability of an earthquake occurring on a certain day in a certain area is 0.05, what are the odds against an earthquake?
A) 19 to 1
B) 1 to 20
C) 18 to 1
D) 20 to 1

Question

Quizplus · Accepted Answer

The odds against an event are calculated as the ratio of the probability of the event not happening to the probability of the event happening. Here, the probability of not having an earthquake is 1 - 0.05 = 0.95. The odds against an earthquake are therefore 0.95 to 0.05, which simplifies to 19 to 1.

If It Has Been Determined That the Probability of an Earthquake