計算氣體里程效率

Question

由於優質汽油比普通汽油更昂貴，所以我需要計算必須使用優質汽油的汽油里程來彌補普通汽油的成本差異。該值由gasmileageRequired變量表示。

問題：我是否正確計算了gasmileageRequired變量？

import java.text.DecimalFormat; 
    import java.text.NumberFormat; 
    import java.util.Scanner; 

    public class GasMileage { 
    public static void main(String[] args) { 

     //Variable declarations 
     Scanner scan = new Scanner(System.in); 
     NumberFormat numFmt = new DecimalFormat("##.###"); 
     NumberFormat costFmt = DecimalFormat.getCurrencyInstance(); 

     double tankSize = 0; 
     final double regularCost; 
     final double premiumCost; 
     double regularGasMileage = 0; 


     //User enters gas tank size 
     System.out.print("What is the size of your gas tank? (in gallons) "); 
     tankSize = scan.nextDouble(); 

     //User enters price of regular gasoline 
     System.out.print("What is the cost of regular gasoline per gallon? (in $) "); 
     regularCost = scan.nextDouble(); 

     //User enters price of premium gasoline 
     System.out.print("What is the cost of premium gasoline per gallon? (in $) "); 
     premiumCost = scan.nextDouble(); 

     //User enters cars' gas mileage 
     System.out.print("What is your cars' gas mileage on regular gasoline? (miles/gallon) "); 
     regularGasMileage = scan.nextDouble(); 

     //Variable declarations 
     double totalregularCost = regularCost * tankSize; 
     double totalpremiumCost = premiumCost * tankSize; 
     double costDifference = totalpremiumCost - totalregularCost; 
     double gasmileageRequired = regularGasMileage + (premiumCost/costDifference); 
     scan.close(); 

     //Begin output 
     System.out.println("\nGas tank size: " + tankSize + " gallons"); 
     System.out.println("\nTotal cost of regular gasoline: " + costFmt.format(totalregularCost) + "\nGas mileage (regular): " + numFmt.format(regularGasMileage) + " miles/gallon"); 
     System.out.println("\nTotal cost of premium gasoline: " + costFmt.format(totalpremiumCost) + "\nGas mileage required to make up for cost increase: " + 
     numFmt.format(gasmileageRequired) + " miles/gallon"); 
    } 
} 

Answer 1

gasmilage需要正確計算，是的。它應該告訴你需要多少MPG才能彌補價格差異。