At what rate percent per annum compound interest will 6500 amount to 9251 in 9years? Legend: A = amount after t; P = initial amt deposited; r = rate in %; t = time in years Solution: (approximated) A = P(1 + r)^t 9, 251 = 6, 500(1 + r)^9 (1 + r)^9 = 9, 251/6, 500 (1 + r)^9 = 1.423 (1 + r) = (1.423)^1/9 (1 + r) = 1.04 r = 1.04 - 1 r = 0.04 r = 4%