I find it disturbing that you always want to split rooms with married couples when you travel.
You say the women all have jobs and make money. Kinda sounds like they are doing you a favor since the implication is that they make enough to get their own room and are sharing with you to accommodate you.
If my wife and I had to pay 66%, Id just rather pay the additional 1/3 to not have a guy sleep in the same room. However, if the 3rd person was a woman, I wouldn't charge anything and just request 1 king size bed at check in.

In all seriousness, 30-30-40 seems to make the most sense.While they may be sharing the bed, everything else in the room (TV, closet, etc.), including bathroom, is shared.