If it has been determined that the probability of an earthquake occurring on a certain day in a certain area is 1/20, what are the odds against an earthquake?

1 - 1/20 = ?

0.05 To calculate the odds against an event, you need to determine the probability of the event not occurring. In this case, the probability of an earthquake occurring is 1/20.

To find the probability of an event not occurring, you subtract the probability of the event occurring from 1. Therefore, the probability of no earthquake occurring on the given day in the specified area would be:

1 - (1/20) = 19/20

The odds against an earthquake happening can be expressed as a ratio of the probability of no earthquake occurring to the probability of an earthquake occurring. So, the odds against an earthquake in this case would be:

19/20 : 1/20

Simplifying this ratio gives you:

19 : 1

Therefore, the odds against an earthquake on the specified day in the specified area are 19 to 1.