A discrete probability distribution displays the probability of certain outcomes when there are countable items in the sample space. Marcos performed two experiments with countable results. The first was to roll 2 number cubes 20 times, and record the different sums. He made a graph of the results, and checked to make sure that the sum of the probabilities added to 100%. He the started an experiment where he tossed 4 coins and recorded the number of tails that occurred from each toss. He had time to complete the experiment, but will have to continue the graph the next session.