How many years does it take an investment to triple in value if it is invested at 7.5% compounded monthly? Round your answer to 2 decimal places. Solution Future value of investment = initial investment * (1 + i/n)^(t*n) where i = interest per year = 7.5% n = number of periods in a year = 12 t = number of years, amount is invested let X be the initial investment => future value = 2X => X * (1+7.5%/12)^(t*12) = 2X => (1.00625)^12t = 2 => 12t = ln(2)/ln(1.00625) => t = 9.27 years .........ans.

1. How many years does it take an investment to triple in value if it is invested at 7.5%
compounded monthly? Round your answer to 2 decimal places.
Solution
Future value of investment = initial investment * (1 + i/n)^(t*n)
where
i = interest per year = 7.5%
n = number of periods in a year = 12
t = number of years, amount is invested
let X be the initial investment
=>
future value = 2X
=>
X * (1+7.5%/12)^(t*12) = 2X
=>
(1.00625)^12t = 2
=>
12t = ln(2)/ln(1.00625)
=>
t = 9.27 years .........ans