You are beginning a college savings plan to cover tuition for your two children. To do that, you will deposit money into a fund each month, starting next month, for 15 years. After that time, any money in the fund will continue to earn interest, even though no additional deposits are being made. The fund's rate of return is expected to be 7% APR, compounded monthly.

Child #1 will enroll in a college in 15 years, be enrolled for 4 years, and pay tuition at the beginning of each year of $50,000 annually. Child #2 will enroll at another school two years later, be enrolled for 5 years, and pay tuition at the beginning of each year of $7000.

How much must your monthly deposit be?