Definitions for "Theoretical Probability"
a numerical measure of the likelihood that an event will occur; the ratio of the number or proportion of successes or favorable outcomes in the sample space to the number of outcomes in the sample space; the expected results (see also experimental probability); for example if a coin is flipped 50 times with 30 heads and 20 tails, the experimental probability of heads is 30/50 or .6; whereas, the theoretical probability for obtaining heads is 25/50 or 1/2 or .5
Probability that is determined on the basis of reasoning, not through experimentation.
the ratio of the number of favourable outcomes (what you want to happen) to the number of possible outcomes (what could happen)