How to get average from given values

Question

How do I average?. I am suppose to find the average of the GPA, total of students, and the total of GPA. example:

input: 4

Answer 1

If the problem is that you're getting the wrong answer, the reason is this loop:

while (GPA >=0)
{
    GPA = keyboard.nextDouble();
    total = total + GPA;
    count++;
}

Presumably you intend the loop to exit when the user enters a negative number. What's wrong with it is that it will include the negative number in the total and count. You can rewrite the loop like this:

GPA = keyboard.nextDouble();
while (GPA >=0)
{
    total = total + GPA;
    count++;
    GPA = keyboard.nextDouble();
}

(Other solutions are possible). Later in your code, you will need to guard against the first number being negative. If that happens, count will be 0 and you want to avoid dividing by 0 and printing nonsense results.