If a genetics experiment yields 428 green peas and 152 yellow peas, estimate the probability of getting an offpring pea that is green.
Does that probability change if the experiment is repeated?
By computing the percent of peas which are green, we get 73.8% which is close to Mendel's theoretically predicted result of 75%.
Note: 73.8% is the exact probability of selecting a single green pea from the 580 peas in the experiment.
If the peas and process in the experiment are representative of all such future experiments, then 73.8% is also a "predictor" of all such experiments in that we can expect a result of approximately 73.8% in future experiments.
Of course future experiments are unlikely to produce exactly 73.8% green peas because of uncertainty due to random chance. Thus we use the phrase "probability of 73.8%" to qualify our prediction.
In later chapters, we will learn to estimate not only the percent of green peas, but also the uncertainty of our estimate.