There was this crazy banknote forger that decided to make $21 dollar face value notes, suggesting that they are very rare. He offered one to a banknote collector, who said to him:
"I have some rare banknotes as well. How would you like your $21 dollar note exchanged? For three sevens, or seven threes?"
"I have some rare banknotes as well. How would you like your $21 dollar note exchanged? For three sevens, or seven threes?"


















