Question

Drivers are concerned with the mileage obtained by their automobiles. One driver has kept track of several tankful of gasoline by recording miles driven and gallons used for each tankful. Develop a C++ program that inputs the miles driven and gallons used for each tankful. The program should calculate and display the miles per gallon obtained for each tankful and print the combined miles per gallon obtained for all tankful up to this point. (Use the five-step problem solving methodology)

The results should look like the following:


Enter the miles used (-1 to quit): 287

Enter gallons: 13

MPG this tankful: 22.076923

Total MPG: 22.076923

Enter the miles used (-1 to quit): 200

Enter gallons: 10 MPG this tankful: 20.000000

Total MPG: 21.173913

Enter the miles used (-1 to quit): -1

Answer 1

#include <iostream>

using namespace std;

int main() {
    int miles, gallons, totalMiles = 0, totalGallons = 0;
    while (true) {
        cout << "Enter the miles used (-1 to quit): ";
        cin >> miles;
        if (miles == -1)
            break;
        cout << "Enter gallons: ";
        cin >> gallons;
        cout << "MPG this tankful: " << miles/(double)gallons << endl;
        totalGallons += gallons;
        totalMiles += miles;
        cout << "Total MPG: " << totalMiles/(double)totalGallons << endl << endl;
    }
    return 0;
}