Final answer:
The probability that a couple's next child will be male is 50 percent, as each pregnancy is an independent event with an equal chance of resulting in a boy or girl.
Step-by-step explanation:
The probability that a couple's next child will be male or female is an example of a simple event in probability with only two possible outcomes often referred to as a binomial probability. Since the sex of a baby is determined by whether the father passes on an X chromosome or a Y chromosome, and since a mother can only pass on an X chromosome, each pregnancy has an independent 50 percent chance of resulting in a male (XY) or a female (XX) child.
Therefore, even if a couple has a boy already, the probability that their next child will also be a boy is still 50 percent. This is because the outcome of one pregnancy does not influence the outcome of another. It's important to note that this is true under normal biological circumstances, assuming no other factors influencing gender determination.