Loosely speaking the situation will be something like this: females will say I got As in history and English and B’s in Science and Math, therefore, I should follow my strengthens and specialize in drawing on the same skills as history and English. Boys will say I got B’s in Science and Math and C’s in history and English, therefore, I should follow my strengths and do something involving Science and Math.
This analysis done by females can be understood using Marginal analysis, i.e., if MCMath > MCEnglish for females, then the MC of doing math is greater than that of English, so they devote more effort to English. However, this ignores the hidden benefits of studying Math. It is more likely that (MRMath-MCMath) > (MREnglish-MCEnglish). or that the marginal profitability of Math is greater than that of English. The expressions in parentheses are the marginal profitability of each activity.