Question 12 Assignment

#include <stdio.h>
double grade();
double percentage();
double sum=0;
int main()
{

    printf("\nThe percentage of the grade is %.2lf",percentage(grade()));
    return 0;
}

double grade()
{
    double result=0,average=0;
    int counter;
    printf("Each course is out of a 100\n");
    printf("Enter 3 courses result \n");
    for(counter=0;counter<=2;counter++)
    {
        scanf("%lf",&result);
        sum=sum+result;
    }
    //average=result/3;
    printf("The average grade is %.2lf\n",sum/3);
    return sum;
}
double percentage(double sum)
{
    return (sum/300)*100;
}