A amount doubles itself in 15 years. what is the rate of interest?

A amount doubles itself in 15 years. what is the rate of interest?

Quiz

Answer/Solution

20/3 %

Steps/Work

let amount be x & rate of interest be r% annual then
(2x-x)=(x*15*r)/100
=> 15r = 100
=> r=20/3 %
ANSWER:A