This is a problem from Discrete Mathematics and its Applications
My question is on 10g. Here is my work so far.
My logic behind this is to first iterate over all peoples in the world, for each person in the world, again iterate over all peoples in the world. This is going to find a combination of two unique people(bc of x != y) that Nancy can fool. How can i put a quantifier or check to make sure that this is the only combination? After all, one the main tools that I was given represents "there is". It doesn't check exact amount(in this case 2). I don't what this would be called but I tried looking up exact quantifiers(a logical guess) - https://www.google.com/#q=exact+quantifiers but didn't find anything on this subject - it was all stuff on regular expressions, php, regex, asymmetrics, etc.