Answer:
23.4 years.
Step-by-step explanation:
7400 dollars is placed in an account with an annual interest rate of 7%.
Now, let us assume that the interest is compounded annually and it will take x years for account value to reach 36000 dollars.
Hence, from the formula of compound interest, we can write that
[tex]36000 = 7400(1 + \frac{7}{100})^{x}[/tex]
⇒ [tex](1.07)^{x} = 4.865[/tex]
Taking ln both sides we get,
x ln (1.07) = ln (4.865)
⇒ x = 23.4 years.
