According to Goldin, educated women generally make less than educated men even though they have the same level of education and work in the same industries. She rejects discrimination as the main cause as data does not support that hypothesis. Goldin argues that at the start of their careers, men and women earn more or less the same wages and salaries. But as time passes, men's incomes increase faster than women's. Why?

Consider Catherine and Phillip an educated couple in California. Both husband and wife have master's degrees in corporate finance. They are both making $85,000 per year working for a financial services firm. They both have "greedy jobs", meaning inflexible demanding jobs with long hours. They have to work about 10 hours a day and be in the office all the time. Then they decide to have a child. Now they have a decision to make. Catherine can continue in her current demanding position, but then the couple have to place the kid in a daycare center. Daycare costs are quite high in the U.S. Assume that the cost of daycare in California is $25,000 per year. The alternative is for Catherine to request to move to a less demanding position with flexible hours and teleworking possibilities, in which case her annual salary will drop to $75,000 but she will be able to take care of the baby with the help of a part-time babysitter. The cost of the babysitter will be $5,000 per year.

what is the marginal cost of moving to the more flexible position in dollars per year?

what is the marginal benefit of the move in dollars per year?