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When evaluating attractiveness of girls in a potential threesome one must use the following equation:

x=The overall hottness of first girl (0-10 scale)
y=The overall hottness of second girl (0-10 scale)

z= Average hottness of the two girls (0-10)/2
Alex plans on having a threesome with two girls.
He tells his friends that they are both 6's
however using the Barresi Principle he explains that the overall hotness of the encounter equals at 8.4

(6*0.20)+(6*0.20)+6 = 8.4

The Barresi Principle Demonstrates that if one is to sleep with two 6's, it is the equivalent of sleeping with one 8.4!
by cscott92 May 14, 2011