III.21. Mendel’s peas. Gregor Mendel used garden peas in some of the experiments that revealed that inheritance operates randomly. The seed color of Mendel’s peas can be either green or yellow. Suppose we produce seeds by “crossing’’ two plants, both of which carry the G (green) and Y (yellow) genes. Each parent has probability 1-in-2 of passing each of its genes to a seed, independently of the other parent. A seed will be yellow unless both parents contribute the G gene. Seeds that get two G genes are green.

What is the probability that a seed from this cross will be green? Set up a simulation to answer this question, and estimate the probability from 25 repetitions. (Hint: See page 447.)