I'm giving an on line dye class right now. One assignment I handed out was to choose three primaries and make four distinctly different colours from them.
Red Blue Yellow
Turquoise Magenta Yellow
Orange Purple Green
Inspired by this to spot dye a pan full of nylons in each set I was amazed by the range of colours created from three.
Here is a pair from each pan.
Left to Right Orange Purple Green/ Turquoise Magenta Yellow / Red Blue Yellow