Scenario 1: The mother has both of her X chromosomes go into her egg, which is then fertilized by a sperm with a Y chromosome. Scenario 2: The father has both his X chromosome and his Y chromosome go into his sperm, which then fertilizes an egg with one X chromosome.
Work Step by Step
To figure this problem out, first consider the normal genetic makeup of males (XY) and females (XX). Then construct scenarios in which an extra X chromosome ends up in a gamete but in which a Y chromosome can also be found in the resulting child.