Question

A sum of money becomes 8/5 of itself in 5 years at a certain rate of simple interest . Find the rate of interest?​

Answer 1

Answer:

let the principal is Rs x

principal+ interest=Rs 8x/5

interest =(8x/5-x)Rs=(8x-5x)/5Rs=Rs 3x/5

rate of interest =r %

we know,

interest=rate of interest×principal×time/100

=> 3x/5=r*x*5/100

=> 3/5=r*5/100

=> r=3*100/5*5

=> r=3*4=12

rate of interest is 12 %