I did this exercise based on Colors 101 at Acrylic University. 

The top one was created with Ultramarine Blue (PB29), Anthraquinone Red (PR177) and Cad-Free Yellow Medium (as well as Titanium White).

The bottom one was created with Anthraquinone Blue (PB60), Pyrrole Red (PR254) and Azo Yellow Medium (PY74).