At 5.5 percent interest, how long does it take to quadruple it?
25.89 years.
Solution
(Capital sum) X (1.055)^x = 4 X (Capital sum)
(1.055)^x = 4
take logs of both sides
x ln(1.055) =ln4
x = ln(4) / ln (1.055)
= 25.89
At a simple interest rate of 5.5%
4 = (1.055)^n
n=25.89 years
