Mini-exercise

Write a method on Student that returns the student’s Grade Point Average, or GPA. A GPA is defined as the number of points earned divided by the number of credits taken. For the example above, Jane earned (9 + 16 = 25) points while taking (3 + 4 = 7) credits, making her GPA (25 / 7 = 3.57).

Note: Points in most American universities range from 4 per credit for an A, down to 1 point for a D (with an F being 0 points). For this exercise, you may of course use any scale that you want!