Your cousin Ray borrows $1600 now, repays $800 in two years, and then borrows $1000 in another three years, all at nominal rates of interest of 7.5% convertible quarterly. At the same interest rate, t years from now, your other cousin Jay borrows $1800. If the present value of each of your cousin's debts is the same, what is t? (Assume compound interest at all times.)