Question

Solve for the unknown interest rate in each of the following: (Do not round intermediate calculations. Enter your answers as a percent rounded to 2 decimal places, e.g., 32.16.)
  

Present Value					Years		Interest Rate		Future Value
	$	160			4			%	$	192
		280			18					733
		31,000			19					128,034
		30,261			25					350,964

Answer 1

FV = $192 = $160(1 + r)⁴

r = ($192 / $160)^1/4 – 1 = 4.66%

FV = $733 = $280(1 + r)¹⁸

r = ($733 / $280)^1/18 – 1 = 5.49%

FV = $128,034 = $31,000(1 + r)¹⁹

r = ($128,034 / $31,000)^1/19 – 1 = 7.75%

FV = $350,964 = $30,261(1 + r)²⁵

r = ($350,964 / $30,261)^1/25 – 1 = 10.30%