Question

(b) Find the rate of interest if a sum of money gets doubled in 8 years​

Answer 1

Let the sum (P) be ₹100

Then Amount(A) = ₹200

Then Interest (I) = ₹200-₹100 = ₹100

Time(T) = 8 years

Therefore, Rate(R) = I×100/P×T

= 100×100/100×8

= 25/2%

=12.5% p.a.

Therefore, the required rate of interest is 12.5% p.a. (Ans.)