What does being Hispanic have to do with it.
So multiply all your grades (4.3 for A+ 3.0 for B etc) by the units that the class is worth (ranges from about 2 to 5). Then divide by 4 times the units the class is worth.
Example. You have 2 grades, A+ for a 3 unit class and B+ for a 4 unit class so ((4.3x3) + (3.3x4)) / (4x3 + 4x4)= somewhere around 3.7