Question

Use the compound interest formula A = P(1 + r) and the given information to solve for r.

Answer 1

$\textbf{Answer:}$

$r\approx 0.13345$

$\textbf{Step-by-step explanation:}$

$\text{Your formula is missing something: t}$

$\text{It should read }A=P(1+r)^t$ $\text{Where A is the final amount, P is the principal, r is rate in decimal, and t is time in years}$

$\text{Given that A=3000000, P=20000, and t=40, we can subsitute and solve}$

$A=P(1+r)^t$

$\text{subsitute}$

$3000000=20000(1+r)^{40}$$\text{ now solve for r}$

$\text{Divide both sides by 20000}$

$150=(1+r)^{40}$

$\text{Take the 40th root of both sides }(\sqrt[40]{})$

$\sqrt[40]{150}=1+r$

$\text{subtract 1 from both sides}$

$\sqrt[40]{150}-1=r$ $\text{ or in approximate form, }$[/tex]r\approx 0.13345[/tex]

Answer 2

Step-by-step explanation:

A=P(1+R)

A/P=1+R

(A/P)-1=r

(3000000/20000)-1=r

149=r