I think ar, if they used this method to mention the giving and
returning of money, sure the 1 dollar will remain a
mystery...
But if the 5 dollars is with the clerk, and 25 dollars in the cash
register, he returns 3 dollars and have 2 more dollars with him.
Like that, we still can amount to 30 dollars... This is provided if
they each pay 10 dollars in the beginning...
But if the three fellas give initially 27 dollars, then there is no
need to refund liau coz the man getting the money won't have any
left over money to refund...
Aih, I donno what I am talking... hahaha
