Another variation is the Waterfall mixer, that works more or less that in the Right side on the Dance floor the ladies make a line and in the Left side the Gentleman, then dance to about 3/4s of the dance floor and each goes back to the line, that way everyone gets to dance.
Usually most mixers last between 8-12 minutes, very much depends on how many people participate.
Here in AZ, they have "Singles" dances, but everyone is welcome, and regular dances too.
Keep in mind that this state is one of the two largest retirement communities in USA, so, there are dances basically 6-7 days at week, check this web site, and this is only one of the dance schedules.
http://members.cox.net/arizonaballroom/


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mdorantes