A party of three people go to a restaurant. The dinner is $10 a head so a total cost of $30, as they are regulars the manger gives them a discount of $5. The waiter decides it’s to hard to split the $5 so he keeps $2 and gives them back a $1 each. The meals are now $9 each therefore making it a total of $27, the waiter kept $2 giving a total of $29. Where did the $1 go?