ABSTRACT
This chapter offers to puzzle solvers a piece or advice that might seem obvious, but is frequently overlooked: change the numbers! Often a puzzle is stated using numbers that are too large to deal with, but solvers take to be sacred. Better to replace them with numbers that are small enough to see what's going on; then, later, it may be clear how to return to the original problem statement. Ten puzzles and a theorem are offered to make this case; among them problems with dominoes on a chessboard, spinning switched, lost boarding passes, flying saucers, gasoline shortages, coins on a table, and sharing coconuts with a monkey. The theorem shows how one can design a daily pairing of combatants in a dojo in such a way that each student gets to spar once with every other one.
