100/2 = <<100/2=50>>50 people in the theater have brown eyes.
100/4 = <<100/4=25>>25 people in the theater have black eyes.
There are 50+25+19 = <<50+25+19=94>>94 people in the theater with either brown, black, or blue eyes.
There are 100-94 = <<100-94=6>>6 people in the theater with green eyes.
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