[robbrown451]

Magenta yellow and cyan are subtractive primaries. Cyan might pass for blue, but magenta really isn't red.

And really you could say red green and blue are subtractive primaries (as well as additive), but we use cyan ink because it subtracts red light. (etc)

[a-nikolaev]

Yeah, technically yes, but the poster above refers to the primary colors used in arts, which are red, blue, and yellow. They do represent subtractive colors magenta, cyan, yellow.

[robbrown451]

I'd say red yellow and blue is used in elementary school art class, and not much more. And even then, kids almost always have more colors to work with than three.

The subtractive color model isn't really good for paints anyway, it is best with translucent inks/dyes, where the white from the paper comes through.