Question

Twenty years ago A borrowed some money from B. Now the amount has become twice the principal
Find the rate of simple interest percent per annum.​

Answer 1

let Principle amount be x

and

Rate of interest be r

also given total interest = 2x

since,

Simple Interest = PRT / 100,

therefore,

2x = xr20 / 100

r = 2x * 100 / 20 x

r = 10

Answer 2

Answer:

Let Borreed money =P

time 20years

Amount =2P

interest=2P-P

=P

R=?

I=PTR/100

P=P*20*R/100

R=100/20

=5%