Answer
225 dollars
Work Step by Step
I=PRT
Let P=1500dollars , R=20% ,T = 9 months
9 months =$\frac{9}{12}$year=$\frac{3}{4}$ year
I=1500 $\times$20% $\times$ $\frac{3}{4}$
Write 20% as a decimal
I = 1500$\times$0.2 $\times$ $\frac{3}{4}$
Multiply
I=300$\times$ $\frac{3}{4}$ =$\frac{900}{4}$ = 225
The simple interest is 225 dollars.