Solve for the unknown interest rate in each of the following (Do not include the percent signs (%). Enter rounded answers as directed, but do not use the rounded numbers in intermediate calculations. Round your answers to 2 decimal places (e.g., 32.16)):
Present Value Years Interest Rate Future Value
$ 715 6 % $ 1,381
905 7 % 1,718
15,000 18 % 141,832
70,300 21 % 312,815