A little numerical exercise:

red = 3 + 5 = 8                 magenta = 24 + 5 = 29

black = 10 + 5 = 15                   green = 6 + 5 + 10 = 21

73 is a numinous number. Not only does it represent 1 / 5 of the year - 73 being a mirror image of 5, the black difference between 365 and 360 - but also a period of Venus. Notably also Barthel has sniffed around here.

And I remember that I haven't delivered the answer to the riddle about those 5 sailors and the coconuts. You will find it here.