```
Money spent = (Distance / MPG) * Price per gallon
```
In this case, the distance is 2500 miles, the MPG is 15, and the price per gallon is $1.80. Plugging these values into the formula, we get:
```
Money spent = (2500 miles / 15 MPG) * $1.80 per gallon
```
```
Money spent = 166.67 gallons * $1.80 per gallon
```
```
Money spent = $300.01
```
Therefore, you will spend $300.01 on gas for your 2500-mile trip.