Answer:
4 years
Explanation:
Simple Interest is calculated using the formula below
I= P x r x t
Where I = Interest
p= principal
r= interest rate
t= time in years
In this case
I=81
p=450
r=4.5 % or 0.045
t=???
Therefore;
81= 450 x 0.045 x t
81=20.25t
t=81/20.25
t=4
It will take four years