Answer:
This problem requires us to calculate the value of investment after 25 and effective rate of return. Investment value after 10 years and initial investment amount is given in the question.
Rate of return (r)
18,321.04 = 15,000(1+r)^10
Log 1.22 = 10 log(1+r)
r = 2%
Value of investment after 25 year = 15,000(1+2%)^25 = $ 24,609