1 #include<stdio.h>
2 int main(void)
3 {
4 float gallons=0,miles,TotGallons=0,TotMiles=0;
5 while (gallons!=-1)
6 {
7 printf("Enter the gallons used (-1 to end):");
8 scanf("%f",&gallons);
9
10 if(gallons!=-1)
11 {
12 printf("Enter the miles driven:");
13 scanf("%f",&miles);
14 printf("The miles / gallon for this tank was: %f\n",miles/gallons);
15 TotGallons+=gallons;
16 TotMiles+=miles;
17 }
18 }
19 printf("\n");
20 printf("The overall average miles/gallon was : %f\n",TotMiles/TotGallons);
21 return 0;
22 }
