Hello, Simone!

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.