Given the dimension of the sauce pan

The sauce pan is cylindrical in shape, the volume of a cylinder is given as

The volume of the sauce pan will be

If the pan is filled half way, then the volume of the sauce is

The meatball is spherical in shape, it has a diameter of 1 inch, the volume of a sphere is

Hence, the volume is given by,

So, 5 meat balls are in one serving, therefore the volume for one serving will be

The volume of two servings of meat ball will be

Comparing the volume of sauce (25 cubic inches) he made in the pan and the volume of 2 meatballs (5.2 cubic inches) servings, we can confidently say he will be able to get two servings of meatballs from the sauce pan
Hence, he is able to get 2 servings of meatballs