Mathematics Homework Help

The controller (money manager) for a small company puts some money in the bank account paying 4% per year. He uses some additional money. amounting to 1/3 the amount in the bank, to buy bonds paying 5% per year. With the balance of the funds, he buys a 9% certificate of deposit. The first year the investments bring a return of $672. If the total of the investment is $10,000 how much is invested at each rate?

The amount in the bank account is $???, amount in bonds $???, certificate deposit $???