What is the rate on an investment that doubles $5051 in 9 years? Assume interest is compounded quarterly.

Answer: The rate at which the investment gets double is 7.776 Step-by-step explanation:Given as :The principal investment = $ 5051The time period of investment = 9 yearsLet The rate of interest = R % compounded quarterly The Amount gets double So,  From Compounded methodAmount = Principal ×[tex](1+\dfrac{rate}{4\times 100})^{4\times Time}[/tex]Or, 2 × P = P  × ( 1 + [tex]\dfrac{\textrm R}{400})^{\textrm 36}[/tex]Or, 2 =  ( 1 + [tex]\dfrac{\textrm R}{400})^{\textrm 36}[/tex] Or, [tex]2^{\frac{1}{36}}[/tex] = 1 + [tex]\dfrac{\textrm R}{400}[/tex]or, 1.01944 - 1 =  [tex]\dfrac{\textrm R}{400}[/tex]or, 0.01944 =  [tex]\dfrac{\textrm R}{400}[/tex]∴ R = 0.01944 × 400 = 7.776Hence The rate at which the investment gets double is 7.776   Answer