Answer:
The number of years is [tex]T =13 \ years[/tex]
Explanation:
From the question we are told that
The total value of the investment A and B is [tex]k =[/tex]$40, 000
The future value of A is [tex]F_A =[/tex]$28,000
The time period is t = 3
The expected return of A is [tex]e_A =[/tex] 7.1 % = 0.071
The future value of B is [tex]F_B =[/tex]$36,000
The time period for B is T
The expected return of B is [tex]e_B =[/tex]5.5 % = 0.055
The present value of investment A is mathematically represented as
[tex]A = \frac{F_A }{(1 + e_A) ^t}[/tex]
substituting values
[tex]A = \frac{ 28000 }{(1 + 0.071) ^3}[/tex]
[tex]A =[/tex]$ 22792.38
The present value of B is mathematically evaluated as
[tex]B = k - A[/tex]
substituting values
B = 40, 000 - 22792.38
B = $17,208
The future value of B is
[tex]F_B = B * (1 + e_B)^T[/tex]
substituting values
[tex]36,000 =17,208 * (1 + 0.055)^T[/tex]
[tex]2.0921 = (1.055)^T[/tex]
take log of both sides
[tex]log(2.0921) =log (1.055)^T[/tex]
[tex]0.32057 = T log (1.055)[/tex]
=> [tex]T = \frac{0.3206}{0.0232}[/tex]
[tex]T =13 \ years[/tex]