1) Theoretical probability is calculated by dividing the number of favorable outcomes by the total possible outcomes. 2) For coin flips, the theoretical probability of heads is 1/2 or 50% since there is 1 favorable outcome (heads) out of the total 2 possible outcomes (heads or tails). 3) The theoretical probability of rolling a 3 on a dice and flipping a head is 1/12 or 8.3% since there is 1 favorable outcome out of the total 12 possible outcomes.