We have the next formula to the simple interest
![I=P* r* t](https://img.qammunity.org/2023/formulas/mathematics/college/s8rh2a085vhgdh4zf2iykcqplw0w7zr6is.png)
where
I= interest earn after t years
P is the initial deposit
r is the rate
t is the time
P=1500
r=2.5%
t= 4 years
then we substitute the values in the formula
![I=1500(.025)(4)](https://img.qammunity.org/2023/formulas/mathematics/college/4ffsw48ck8njodww4gpo2kyugtml8bqw46.png)
![I=150](https://img.qammunity.org/2023/formulas/mathematics/college/ailajw3zy6j6o6d4c2fcxbyc0ogpxf22sl.png)
He will earn $150 after 4 years, his final capital will be $1650