Question

Find the rate at which a sum doubles itself in 3 years if interest is compounded anually.​

Answer 1

Answer:

24% p.a.

A sum doubles itself in 3 years at 24% p.a. (approx.) Use rule of 72. Divide 72 by rate of interest to know years to double the amount and divide 72 by number of years to know rate of interest. A sum of money becomes 5 times of itself in 25 years at simple interest.