Question

In how many years will rs.8000 amount to rs.9261 at 5% per annum compounded annualy ?

Answer 1

Amount=9261
Principle=8000
rate=5 percent

a=p×(1+r/100)^n

9261=8000 (1+5/100)^n
9261/8000=(21/20)^n

hence 9261 is the cube of 21 and 8000 is the cube of 20,then

(21/20)^3=(21/20)^n
.
. . n=3 years
time =3 years