gistfile1.java

import java.util.Scanner;
 
class Car {
	//instance variables
	double start, end, galls;

	//constructor
	Car(double start, double end, double galls) {
		this.start = start;
		this.end   = end;
		this.galls = galls;
	}

	//methods
	double mpg() {
		return (end-start)/galls;
	}

	boolean gasHog() {
		return mpg() < 15;
	}

	boolean economyCar() {
		return mpg() > 30;
	}

	public static void main (String[] args) {
		// get data
		Scanner keyboard = new Scanner(System.in);
		System.out.println("Enter first reading!");
		double start = keyboard.nextDouble();

		System.out.println("Enter second reading!");
		double end = keyboard.nextDouble();
		
		System.out.println("Enter gallons!");
		double galls = keyboard.nextDouble();

		// create car object and call methods
		Car car1 = new Car(start, end, galls);
		System.out.println("\nMiles per gallon: " + car1.mpg());

		if(car1.gasHog()) {
			System.out.println("Gas Hog!");
		}

		if(car1.economyCar()) {
			System.out.println("Economy Car!");
		}
	}
}