But things are more complicated when you consider that the primary colours in your printer are magenta, yellow and cyan, or that the screen you're watching this on uses red, green and blue!
" It is not for you to decide what the Ministry of Magic does or does not do, Dumbledore! " snapped Fudge, now a shade of magenta of which Uncle Vernon would have been proud.
As you can see, pink, purple and magenta can only be made using multiple frequencies of light - there is no single frequency of light that's pink - and of course, white light is a mixture as well!