At what rate percent per annum will a sum of money double in 8 years ?

Dear Student!

Here is the answer to your query.

Let the principal amount and the rate of interest be P and R% per annum respectively.

Given : Time (T) = 8 years

and Sum of money doubles itself

⇒ 2P = P + Simple Interest

∴ The rate of interest for which the sum of money doubles itself in 8 years is 12.5% per annum.

Cheers!