In school, it was always difficult to find a class speaker. We solved the problem by making up a ridiculously big number modulo the number of class members. The remainder position on the class list was the new class speaker. The trick was to make up a ridiculously big number that:
- was big enough to dissemble one's intention not to be class speaker
- was told fluently enough to make an absolutely random impression
- did not deliver a remainder that was congruent with one's position on the class list.