The interest is computed as:
[tex]Interest=Principal*Rate*Time[/tex]
We have the interest as 450, the principal as 3,000 and the time as 1 since it is annual. We substitute the values and get:
[tex]450=3000*Rate*1
[/tex]
We divide both sides by 3000 to leave the rate at the right-hand side
[tex] \frac{450}{3000} = \frac{3000*Rate}{3000} \\ 0.15=Rate[/tex]
The rate is expressed in percent so we multiply 0.15 by 100 and get 15%
