Fish with Mercury: Fish that contain high levels of mercury should be avoided. Mercury consumed during pregnancy has been linked to developmental delays and brain damage. A sample of these types of fish includes: shark, swordfish, king mackerel, and tilefish.
P(A or B) = P(A) + P(B) Addition Rule 2:: When two events, A and B, are non-mutually exclusive, there is some overlap between these events. The probability that A or B will occur is the sum of the probability of each event, minus the probability of the overlap.
If just the first and last columns were written, we would have a probability distribution. The relative frequency of a frequency distribution is the probability of the event occurring. This is only true, however, if the events are equally likely. This gives us the formula for classical probability. The probability of an event occurring is the number in the event divided by the number in the sample space. Again, this is only true when the events are equally likely. A classical probability is the relative frequency of each event in the sample space when each event is equally likely.