A certain office supply store stocks 2 sizes of self-stick notepads, each in 4 colors.
The store packs the notepads in packages that contain
either 3 notepads of the same size and color
or 3 notepads of the same size and of 3 different colors.
If the order in which the colors are packed is not considered,
how many different packages of the types described above are possible?
For a type-A package (two sizes, one color), there are:
. . 2 choices of sizes and 4 choices of colors.
There are: possible type-A packages.
For a type-B package (two sizes, three colors), there are:
. . 2 choices of sizes and choices of colors.
There are: . possible type-B packages.
Therefore, there are: . possible packages.