Well I was looking at my danio's trying to sex them making sure they are all females and saw that one of my mollies fins on the underside of it looks different than the other one.
The anal fin on the one I think is a male is a little bit more slender than the females and also has a smaller fin behind the anal fin.
This molly also chases around the other one alot.
Is my she a he?
I also can't get a picture right now so I found this link with examples of female and male platies.
So my "male" has both the fins a female would, but also right behind the last fin is a smaller skinner fin kinda like what a male would have.
I merged your two posts to save some space on the forum. You can also use your "edit" feature at the bottom of every post for corrections and add ons
Thanks!
Ken
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with the, umm you know.. 
good luck with them, maybe now you'll have to add more females to wean off possible harassment by the male molly. Its pretty aggressive and the female doesn't get much rest. Another female takes all of the attention away ( also good hiding plants and even caves ). Maybe eve n2 more females will help if your tank can handle it.. if not, plants and hiding spots helps 
