The interest rate is 2%. To solve, plug your variables into the simple interest rate formula, r = I/Pt, where r represents the rate, I represents interest, P represents your principal (starting) amount of money, and t represents time, and then simplify. (Subtract the final amount from the principal amount to get your interest, $1500.)
r = 1500/(5000*15)
r = 1500/75000
r = .02 or 2%
