Ok, here is the equation, tell me why it does not work? 3 guys go to a Hotel to rent a room. Clerk says its 30 bucks. Each guy gives the clerk 10 bucks [ 10x3=30 ] They go to room. Clerk finds his mistake and calls bellboy over. Tells bellboy, I overcharged these guys 5 dollars. Room is only 25 dollars. Take this 5 dollars to them. Ok, says bellboy and goes to guys room. After they answer door he explains they were over charged 5 dollars. [ 25 + 5 =30 ] Ok, say the guys, give us each back one dollar, and keep 2 for a tip to make it work out. [ 1+1+1+2=5 ] Bellboy does that and leaves with his 2 dollar tip. WTF math is happening. 25 + 5 =30 right? right. OK, now the 3 guys starting out paying 10 dollars each. They now each get back one dollar. [ 10 -1 = 9 ] Now they have only paid 9 dollars each and the bellboy got a 2 dollar tip. 3 x 9 =27 plus the 2 the bellboy got = 29 dollars. WTF ? They started out with paying 30 dollars. If the math works one way, then why not the other? Imagine if this is a business transaction and the numbers are millions. Who gets the missing dollar?